I have a Human Monk, the game has already started and I'm not switching now (unless I restart again... ugh!).

I've maxxed out his WIS and DEX, and given him the Dodge feat.

I'm considering giving him Lightning Reflexes, since Evasion is dependent on a Reflex Save, and I think my level-up stat improvements are going to sink into WIS (the AC benefit is equal, and the better chance of a successful Stunning Fist is more important than an Evasion, at least that's how I feel now).

I have my Wizard cast Mage Armor on my Monk a lot, and that lasts for a long time (my Wizard is only 2nd or 3rd level, so I know it's only going to get better!). Any other advice? TIA

You don't need to evade this early in the game. Spells that can be evaded won't be cast at you so soon. Pick some other feat.
Use bracers on this guy. Cloaks too will help.

Is this that DG monk with 1 Cleric level? Have him memorise all Sanctuaries. And make use of his innate illusion spells.

He's a Human Monk, although I do plan on adding 1 Cleric level later on.

Although the DG monk can get unreal AC early in the game (plus inate mirror image, blur, small size, & racial bonuses), going human can work too. Take the cleric level early, make sure it is compatable with the correct order. Remember, humans can ignore one extra class for XP penalties. So adding extra levels of cleric here and there won't kill ya. Several cleric spells can help a decoy.
You may want to think about just one level of monk. That way, you still get AC bonus from wisdom (no armor though), get on level of cleric for WIS bonuses, then level up as wizard or soceror to take advantage of illusions, stoneskin, MI, etc. Also can be secondary blaster, with backup minor healing. Take one level of Paladin for save bonuses if you want. Yeah, this character is cheezy, but having a decoy character is kinda cheezy to begin with.

I want to remain mostly Monk for the attacks and powers.

I understand, but your monk will do much more damage with a descent STR bonus and a two handed weapon (axe) until he gets to be 20+ level.

You sure, GG? I was thinking of dumping my Greataxe after 5th level, since that's when the extra attacks kick in.

First of all, what are his stats?

Your greataxe does 1D12 damage and adds 1.5Str modifier bonus. Assuming his Str is 18, there is an additional +6 damage.
Monk Fists start doing 1D12 damage at L12; and 1D20 damage at L16. Add to this +4 Str bonus damage.
Thus until you hit L16 you will do more damage with a two-handed axe.

However Monk fists are considered +2 weapons from L13 onwards (+3 L16 onwards). So if you cant find a suitable +2 greataxe, shift to fists when needed.

He's got a 16 STR.

1 attack 1d12 + 7= 8-19
2 attacks 1d6 + 5= 12-22

Put everything into wisdom. Give the monk items which will improve AC. Strength enhancing items also help.

I never used weapons with my monk. Not even at low levels -- it was just too fun watching her beat everyone.

True, it's fun... But if you'd be a decoy, put a little into constitution - you might fail a save and you will get hit every now and then, so you better be prepared. Plus, I suppose your monk may be the target of your own spellcasters' area spells, and I suppose you will go for giving them hard save, DCs, right? I suppose the charisma might be a bit lower, but you can't max everything... My monks tend to have a little lower strength as well, as I'm not thrilled by having any modifier below -1.

That aside, I prefer the monk as a caster-slayer. It worked even better in the more single-player oriented NWN, but it can be effective here as well - especially if you put some ranks in the stealth skills, high speed and a stunning fist can take a mage out of comission easily.

Klorox, I'd hang onto that axe. Fists are concidered bludgeoning weapons. The monsters that always give you trouble, ie undead, golems, oozes, some demons all have damage reduction to BL damage. Keep the axe as a backup. Critical damage X3 for greataxe, not sure what fists do or range (20 only?)
Plus, my monks aways miss more with fists, not sure why.

eh? What do you mean 2 attacks? Do you really get an attack with your left fist? Have you checked your Charecter Records to confirm that?

16Str = +3 damage modifier. 3*1.5 ~ 4.
Axe: 1D12 +4 = 5-17
Fist: 1D6 + 3 = 4-9

Thanks for correcting my math. Monks do not get offhand attacks, but they do gain multiple attacks faster when fighting without a weapon.

6th level Monk BAB (unarmed) is listed at +4/+1, while with a weapon it is just +4.

Edit: Okie i checked my PHB, with 3.0 rules a monk with bab 4 gets Unarmed BAB 4/1. no wonder they changed that in 3.5.

Didnt know they changed Monks BAB ables from 3.0 to 3.5, just shows how little i have bothered about monk i guess.