Another benefit of enlarge person is that it makes your BSF a bigger target.....literally. Attacks on your BSF aren't attacks on you.
That's right. And the Reach is a nice bonus, too.
Think my spells will be kinda:
Expeditious Retreat: By Wizard Domain. Not really awesome, but it is still OK.
Color Spray: By far the best for lvl1 imo. With a bit care not to stun my mates it will be kinda AoE Instant-Kill.
Grease: Useful in nearly all situations. Can even be used on weapons held by foes or I can get a team member out of that grappling orc's hands.
Enlarge Person: You said it.
Silent Image: With a bit imagination and a good idea it can be a fear effect without save for enemies. Also good out of combat.
Summon Monster 1: He should tank some strikes or flank with the party rogue.
Magic Missle: I think it is really the worst choice after looking thru the other spells. At least at level one. But dealing some damage may be useful.
Tenser's Floating Disk: Disk of all uses.