Picking your domains:The only limitation on the bonus domains you can choose as a Sovereign Host is that you can't pick more than 2 domains that belong to the same deity. I will therefore specify deity after deity and write about each of its domains and why you should (or shouldn't) pick that domain.
Alignment domains: Every alignment domain is a bad choice for a domain. The spells are too specific, not good enough, and most likely you already have them on your spell list. The ability to increase your CL for spells with the right descriptor is also pretty lousy.
Boldrei:Community: I guess the +2 competence bonus to diplomacy is nice if you're a diplomancer, but the spells offered here are not only nearly useless, but in most cases you'll have them in your spell list anyway.
Family: Abilities that are based on cleric level are bad for you, since you won't have a lot of those. The spells are pretty horrible, too.
Good: See "Alignment domains".
Law: See "Alignment domains".
Protection: The ability is based on your cleric level (which will be low), and the only spell that might make this domain worth taking is "Antimagic Field" that you get as 6th level spell instead of 8th.
Dol Arrah:GloryGood: See "Alignment domains".
Law: See "Alignment domains".
SunWar: What is it good for? It's good for taking the Holy Warrior reserve feat from CChamp. Also gives you access to some decent spells. It also gives you Weapon Focus with either a longsword or a halberd.
Arawai:Creation: The bonus to CL is rather useless, and the spells aren't all that hot. But since your character probably won't have these spells on her list otherwise, it's still a nice way to increase your spell list.
Good: See "Alignment domains".
Life: Bad ability. Bad spells that you probably already have. Don't take this domain.
Plant: It's pretty nice, offering you some useful spells that usually only druids can cast.
Weather: The problem with weather-based effects is that even if you're not affected by them, the rest of your party is, and most likely the huge/gargantuan/colossal monster you'll be fighting will be more resistant to those effects than your small/medium/large-sized party members.
Olladra:Feast: Ingested poisons are the last kind of poison an active group of adventurers would encounter, and the good spells in this domain will probably already be in your spell list.
Good: See "Alignment domains".
Healing: You'll get better results just by using a wand of Cure Light Wounds or Lesser Vigor between battles.
Luck: The ability to reroll those natural 1's could save you from horrible, gruesome death so many times during the game.
Pride: Again, rerolling natural 1's on saving throws is great. This domain's ability is less useful since it's more specific, but it does grant you access to some nice spells that are usually under the arcane spellcaster's jurisdiction.
Onatar:Artifice: It's the same case as Creation domain, I guess. The ability is a little bit better and so are the spells, but it's still far from being great.
Creation: Read under "Arawai".
Fire: Both the spells and the ability are mediocre, leading to an average rating of "meh".
Good: See "Alignment domains".
Metal: Gain proficiency with a goliath greathammer with a melee character and go to town.
Warforged: If you're playing a warforged or if there's one in your party, he will thank you again and again if you take this domain. If there isn't a warforged or another construct in your party, there really isn't any point in taking this domain.
Dol Dorn:Chaos: See "Alignment domains".
Competition: A +1 bonus on opposed checks may sound tempting, but it isn't worth taking a domain filled with spells you already have.
Good: See "Alignment domains".
Liberation: Charm, compulsion and fear effects can be a real thorn in your side when you fail your saving throw, but this domain doesn't have any new or interesting spells to offer.
Strength: The ability is pretty lousy, what with the 1 round duration and the dependency on your cleric level, but this domain has some awesome spells to add to your list.
War: Read under "Dol Arrah".
Aureon:Force: Nice spells for primary spellcasters and a damage reroll ability for gishes. This domain is excellent. Use the Force.
Knowledge: Increases the caster level for an entire school. Adds a whole lot of useful skills to your class skills. Grants access to the Knowledge Devotion feat. And adds very solid divination spells that usually only belong to arcane spellcasters to your class list. This domain is pure awesome.
Law: See "Alignment domains".
Magic: This lets you use "spell completion" or "spell trigger" items like a wizard half your cleric level, gives you 2nd level free Identify, 6th level Antimagic Field and Mordenkainen's Disjunction. This domain is also pure awesome.
Mind: This domain offers both a nice ability (+2 on bluff, diplomacy and sense motive) and a very excellent choice of new spells to add to your list (various mind reading spells that divine casters don't normally get). Unfortunately, you'll probably be better off picking 2 other domains from Aureon, so you should only take this if you're playing a dimplomancer.
Oracle: Although this offers a +2 CL bonus on divination and 1st level free Identify, it still pales in comparison to Knowledge and magic domains. You'll already have most spells this domain has to offer. It's still a very good domain.
Spell: Anyspell and its greater version are pretty powerful tools. Having Disjunction in the list is also pretty sweet, and the unnamed bonus on spellcraft could come in handy in epic levels.
Balinor:Air: Some nice spells here, but it's not that great of a domain.
Animal: Shapechange. It doesn't matter that the ability is lousy. It doesn't matter that the rest of the spells in this domain are lousy. This freaking gives you
Shapechange!
Celerity: Good for both gishes and primary spellcasters. Increases land speed. Gives you an array of useful spells that you don't normally have, with Time Stop being the cream of the crop.
Earth: I like toying with the idea of a divine spellcaster using Iron Body, thus ignoring the spell failure that arcane spellcasters suffer, but all-in-all, this domain is still of average quality.
Retribution: The "Strike of Vengeance" ability is good for the gishes. The spells are okay, but not great.
Kol Korran:Charm: Excellent for diplomancers. Gives you useful spells that usually give the arcane diplomancers an edge over divine ones, and the ability to boost your charisma by 4 for 1 minute as a free action will come in handy.
Commerce: Nice spell selection, especially with Polymorph any Object at 9th level.
Pact: Spells that you already have, an ability that grants you class skills that you don't really need, and a bad connotation when hearing the word "pact". Not a good choice for a domain.
Trade: Free action Detect Thought based on your charisma is nice for diplomancers. The spells are pretty horrible, though.
Travel: Even if it's based on your cleric level, automatic Freedom of Movement effect is priceless. This also gives you some great new spells.
Wealth: It has pretty lousy spells to offer, and appraise isn't very useful.
Devotion Feats:In Complete Champion it is stated that a domain can traded for a corresponding devotion feat. Since these do not count against the allowed quota of domains you get from each deity in the host, I've decided to write up a separate list for them.
Air Devotion: I used to think this was a so-so feat, but then
AfterCrescent pointed out that it also grants concealment against ranged touch spells.
Animal DevotionChaos Devotion: You can't control where the bonus will go to. You don't want a buff that you can't count on.
Earth Devotion: There are better ways to ignore rough terrain, i.e. ways that you don't need to waste a feat/bonus domain to use.
Fire Devotion: Maybe this could have been decent if it had an energy type that wasn't so often resisted to by enemies.
Good Devotion: The DR is too low to be worth the feat, and the other ability is barely useful and can be achieved with a low level spell. [Thanks for pointing it out,
AfterCrescent]
Healing Devotion: This could save your life, but most likely, it won't.
Knowledge Devotion: If you're a cloistered cleric or an archivist, or if you just start out with the knowledge domain, this is the feat for you. This is basically a free bonus at the beginning of every battle on attack and damage rolls. Good even for primary spellcasters that don't usually resort to regular attacks (since it also applies for touch attacks).
Law Devotion: A huge bonus to AC or attack rolls. This is a must for gishes.
Luck Devotion: This probably won't make a difference when you use it. There was a nice cheesy combo including this feat and a small-sized dagger, but I can't recall it right now and you probably won't use it anyway.
Magic Devotion: This is pretty lame, but it could be useful when what your party really needs on your turn is for you to strike the finishing blow.
Plant Devotion: I always thought fortification was a bit overrated, and the bonus on natural armor isn't that impressive. Still, it's not a horrible feat.
Protection Devotion: Good for buffers. There's a lot of style in putting up a shield in the last second to save your friends from an ambush.
Strength Devotion: [
AfterCrescent - I stand corrected. Thank you for pointing out the usefulness of this feat]
It's basically a MUST have for ANY melee character. ALWAYS have a natural weapon on you? One that's basically a free greatsword? And can be enchanted with items or spells? Who doesn't want that? It's a weapon that grows with you and is always active. On top of that, if you already have some manner of natural weapon, via feat/spell/item, you get a +2 circumstance bonus to THAT weapon's damage and your slam does whichever is higher, the base for the feat or that of your other weapon. That alone makes it amazing.
Sun Devotion: You'll have plenty of other ways to harm undead without wasting a feat on it.
Travel Devotion: Awesome for gishes, this allows you to use a sort of a pseudo-pounce every round for 10 rounds straight.
War Devotion: You most likely won't use defensive fighting often enough for this to be worthwhile
Other domains and devotion feats:The Sovereign Speaker can be easily adapted into any campaign setting and any pantheon of deities. Therefore, I will now discuss domains and devotion feats that you can't get with the Sovereign Host, but might get with a pantheon in your campaign setting.
Domains:Balance: (SpC) If you want to add your wisdom modifier to AC just buy a monk's belt. The spells are pretty lousy as well.
Cavern: (SpC) The only good thing about this domain is Imprisonment, and you can replace it with other, lower level SoD spells.
Celestial: (BoED) You already have those spells and the smiting ability isn't that great when it's based on your cleric level.
City: (RoD) Pretty unique spells, it's just that they're not very useful when you go into dungeons like most adventuring parties do.
Cold: (SpC) You get some new spells, but they're pretty mediocre.
Courage: (SpC) It sucks when you're the target of fear effects, but you don't need to get overly prepared for them.
Craft: (SpC) Fantastic Machine is a nice spell. So are Forcecage and Wall of Stone.
Darkness: (SpC) Grants you Blind-Fight. Nice choice for gishes.
Death: (PHB) Lousy ability, no new spells. Bad domain choice.
Deathbound: (SpC) It's a must-have for necromancers. Gives you some powerful necromancy spells that divine spellcasters don't normally get, and improves your undead creating ability.
Deathless: (Eb) A few nice spells, but not that great all-in-all.
Decay: (Eb) There aren't any worthwhile spells here and the ability sucks.
Destiny: (RoD) Powerful ability and some powerful domain-only spells. It's very good.
Destruction: (PHB) Maybe if you want Disintegrate and Implosion, but I don't think that those two spells are worth taking the entire domain.
Domination: (SpC) This gives you Spell Focus (Enchantment) and a bunch of good enchantment spells to go with it. Not bad at all.
Dragon: (SpC) It's a good domain for diplomancers, what with Voice of the Dragons and adding bluff and intimidate to your class skills.
Dragon Below: (Eb) Grants you Augment Summoning without needing to take the rather useless Spell Focus (Conjuration). Only problem is that you might need Spell Focus to qualify for other feats or prestige classes for summoners.
Dream: (SpC) Dream Sight is an interesting spell, and immunity to fear is a very nice perk.
Drow: (SpC) You can do better than Lightning Reflexes, and the spells aren't all that great.
Dwarf: (SpC) You can do better than Great Fortitude, and the spells aren't all that great.
Elf: (SpC) Great for archers since it gives you Point Blank Shot, otherwise it's not really worth it.
Endurance: (BoED) Nothing too good to see here, except maybe for iron body, but it's 9th level in this domain.
Envy: (SpC) Almost every spell in this domain is worth having and usable, and extra class skills are always a nice thing to have.
Evil: (PHB) See "Alignment domains".
Exorcism: (Eb) You probably have all of this domain's spells already, and the matter of possession barely becomes an issue, EVER.
Fate: (SpC) If most of your character's AC is based on dexterity, you'll want uncanny dodge. Of course, it's not very likely that your character's dexterity will be so high.
Fey: (BoED) Not bad, but definitely not good. A few nice spells but you can do without them.
Gluttony: (SpC) This domain's highlights are Trap the Soul and Baleful Polymorph. Bite of the King is only good if you're a shugenja that can use Giant Size or if you're using Magic Jar (obtainable with the Envy domain). Other than that, this domain is pretty lousy.
Gnome: (SpC) Silent Image has been suggested as the best 1st level spell ever, and now you, the divine spellcaster, can cast it as well.
Greed: (SpC) It's nice to have if you're the party's sneaker, but it's not very useful otherwise.
Halfling: (SpC) Not a good choice unless for some unknown reason you're stuck as playing both the diplomancer and the sneak in your group.
Hatred: (SpC) No new spells or good domain abilities here. Take something else.
Herald: (BoED) Great for diplomancers, what with the +4 bonus on diplomacy and intimidate and the enchantment spells.
Hunger: (SpC) Pretty nice if you're a necromancer. Pretty worthless otherwise.
Illusion: (SpC) Combine with Gnome domain for extra awesomeness.
Inquisition: (SpC) Not really bad, but not really good, either. A bonus on dispel checks will rarely come in handy, and you'll already have most of those spells.
Joy: (BoED) Also great for diplomancers. Just make sure not to mix with Herald domain, because sacred bonuses don't stack.
Lust: (SpC) Good for diplomancers, but there are better domains than this for them.
Madness: (SpC) Some nice spells, but make sure that your character won't use any wisdom based skills.
Meditation: (Eb) Basically, you get Sudden Empower as a bonus feat. It has its uses, but the domain's spells aren't all that great.
Mentalism: (SpC) Even if you're no taking more than 5 levels of your base class, the ability can still save a party member from annoying enchanters. The spells are average.
Moon: (SpC) Only good if there are a lot of lycanthropes in your campaign.
Mysticism (both Good and Evil): (SpC) If you want to add your charisma to your saves, there are better ways than taking this domain. The spells most likely will not be new to your spell list, so there's really no good reason to take this domain.
Necromancy: (Eb) Good for necromancers, obviously.
Nobility: (SpC) This may be an OK choice for diplomancers/enchanters, but it's not very good all-in-all.
Ocean: (SpC) Most adventurers don't encounter enough large bodies of water to actually be able to even try out most of the spells in this domain.
Orc: (SpC) Nothing to offer except for Prying Eyes.
Passion: (Eb) Taking this and the Celerity domain is almost like taking a level of barbarian. Nice for gishes.
Pestilence: (SpC) Immunity to disease is nice, as are some of the spells in this domain.
Planning: (SpC) This gives you Extend Spell (which is part of the DMM [Persistent] cheese chain) as a bonus feat and the 9th level spell is Time Stop.
Pleasure: (BoED) When you need the spells of this domain, you really need them. The only problem is that you won't need them too often and most divine spellcasters already have other spells that have the same needed effect, so it's not a very good domain choice. Charisma-based spellcasters might benefit from the domain's ability, but probably only once during the entire campaign.
Portal: (SpC) Gives you some useful spells for travelling, and if you're in a plane-jumping campaign the domain ability could be useful.
Purification: (SpC) You'll probably already have the domain spells in your class list, and abjuration is considered one of the least useful schools in the game.
Renewal: (SpC) The only reason this isn't a terrible domain is because it gives you access to Polymorph Any Object. There are already better domains that you can get this spell from, so feel free to entirely disregard taking this domain as an option.
Repose: (PGF) Most of the spells here are not so great and you probably already have them on your list, and the ability is awful.
Rune: (SpC) Scribe Scroll can be nice when you have a lot of domains, since you can make scrolls of the domain spells you don't usually have prepared, and it's also an item creation feat, which some PrC's and feats require. The domain's spells aren't too useful, though.
Scalykind: (SpC) It's like Animal domain, only there are more useful spells here other than Shapechange.
Shadow: (Eb) The spells in this domain increase your spell list and versatility by a huge amount. It also gives you Blind-Fight, which is nice if you're a gish.
Slime: (SpC) There are some nice spells here like Evard's Black Tentacles and high-level SoDs. It's not amazing, but not bad.
Sloth: (SpC) The ability could be nice for a gish, and some of the spells are nice for travelling and the likes.
Sky: (RotW) Having spot as a class skill is always useful when wisdom is your most important attribute, but this domain is most useful when your character has a natural fly speed.
Spider: (SpC)Storm: (SpC) Nothing too powerful here, but it's not horrible, either.
Suffering: (SpC) There are very few decent spells here and the ability is lousy. Not really worth taking.
Summoner: (SpC) Like the name suggest, it's excellent for summoners. It's especially useful for druid summoners.
Time: (SpC) This domain is always good to have. It gives you Improved Initiative (which is good for everyone), gishes benefit from having True Strike and primary spellcasters benefit from having Haste, Contingency, Foresight and Time Stop.
Transformation: (RoE) This gives you the entire polymorph chain, except for draconic polymorph. That's just insane. Even if you're a gish, this gives you Enlarge Person.
Trickery: (PHB) Good spells, good skills added to your class. This domain is very good.
Truth: (RoE) It's nice, but you probably already have most of the spells in this domain, and the ability isn't too useful.
Tyranny: (SpC) Good for enchanters, who need as high a DC as they can get.
Undeath: (SpC) This domain is worth having if only for getting Extra Turning. Turn attempt can be used as fuel for many powerful mechanics, where the most notable is Divine Metamagic.
Water: (PHB) The spells are average, the ability isn't really noteworthy. It's an OK domain.
Watery Death: (PGF) Some very nice combat spells in this domain. Not too shabby, but there are better domains.
Wrath: (BoED)Wrath: (SpC) If the ability wasn't based on your cleric level, this could've been a good choice for gishes. Rhino's Rush is nice for melee characters that are not based on ranger or paladin.
Devotion Feats:Death Devotion: Bestow negative levels with your melee weapon. Useful for melee characters, but not overwhelming.
Destruction Devotion: Chip at your opponent's AC every time you deal damage for an entire minute. Good against BBEGs and enemy tanks.
Evil Devotion: Just like with Good Devotion - this feat isn't good.
Trickery Devotion: This feat is so useful it has
an entire thread dedicated to it.
Water Devotion: Summon a water elemental. Useful when your party needs a weak follower to become a corpse (i.e. trigger a trap, attract the attention of something ig and stupid, etc.).