Ok, you may want to take the feat Serenity, which bases paladin things off WIS rather than CHA
[spoiler]Serenity
Type: General
Sources: Dragon #306
Dungeon Compendium Vol. 1
Your wisdom, inner calm and sagacity fuels your class abilities rather than your force of personaility or will.
Prerequisite: Divine grace
Benefit: Use your Wisdom bonus in place of your Charisma bonus for purposes of divine grace, lay on hands, smite evil, and turn undead.
Normal: The abilities use your Charisma bonus.[/spoiler]
Also give thought to the feat Intuitive Attack, which lets you use Wis instead of Str to hit for natural weapons and simple weapons.
[spoiler]Intuitive Attack
Type: Exalted
Source: Book of Exalted Deeds
You fight by faith more than brute strength.
Prerequisite: Base attack bonus +1
Benefit: With a simple weapon of your size or a natural weapon, you may use your Wisdom modifier instead of your Strength modifier on attack rolls.
Special: A fighter may select Intuitive Attack as one of his fighter bonus feats.[/spoiler]
Ascetic Knight helps stack your monk and paladin levels
[spoiler]Ascetic Knight
Type: General
Source: Complete Adventurer
You belong to a special order of religious monks that teaches its adherents that self-enlightenment and honorable service grow from the same well of purity. As a student of this philosophy, you have blended your training as a paladin and as a monk into one seamless whole.
Prerequisite: Improved Unarmed Strike, ability to smite evil.
Benefit: Your paladin and monk levels stack for the purpose of determining your unarmed strike damage. For example, a human 3rd-level paladin/1st-level monk would deal 1d8 points of damage with her unarmed strike.
Your paladin and monk levels also stack when determining the extra damage dealt by your smite evil ability.
In addition, you can multiclass freely between the paladin and monk classes. You must still remain lawful good in order to retain your paladin abilities and take paladin levels, and you must remain lawful in order to continue advancing as a monk. You still face the normal XP penalties for having multiple classes more than one level apart.[/spoiler]
If you can cast paladin spells, try the feat Battle Blessing, which lets you do so as swift actions.
Snap Kick from ToB gives an extra unarmed attack at -2 penalty to all attacks.
Superior Unarmed Strike lets you deal damage as if you were a monk of 4 levels higher. May stack with Monk's Belt. I'd forgo the belt in favor of a Belt of Magnificence gives a boost to all stats.
The +2 version is 25K, the +4 version is 100k, and the +6 version is 200k. Cheaper than buying a bunch of items separately.