Best saves? Check.
Alright, that is true. And Monk needs constitution, dex and wisdom so he winds up those saves even higher.
Lowest difference between attacks (3 v. fighter 5)? Check.
In 3.5 the difference is 5. Also Monk gets 5 attacks with this, with +15 on first one. +15 is low. Fighting classes get +20, when dual wielding its +18/+18/+13/+13/+8/+3. Monk can use kamas, yeah, but it will drop his BAB even lower. And he won't be using this famed 2d10 damage.
Most melee attacks w/o TWF / Tempest type builds? Check.
True. Still... His attacks do crap damage.
More unarmed damage than melee weapons (2d10 @ L20)? Check.
Alright. So a fighter with greatsword reaches around 24-30 str without problems. That's 2d6+15+weapon damage bonuses+epic weapon specialization. He can take classes like weapon master to add incredibly powerful crits to this. And get incredibly high AB with his chosen weapon, if going into epic levels with WM. What does monk do? 2d10+gloves bonus+2 (maybe 3) from strength? No access to weapon spec, and no monk will go for strength in stat increases. Because you have only 32 points. And you need wisdom for your stunning fist and AC. You need constitution for saves and to not die from one hit. You need dexterity for attacks and AC. Str is just less important. I wasn't counting items which would increase stats. Maximum bonus to one stat (+12) still gives a fighter 9 damage and monk just 6.
Free Cleave to get an extra attack w/o burning a feat? Check.
Cleave is quite good, but not gamebreaking. There are better feats around. And fighter gets bonus feat every other level... Gets worse with other fighting classes though.
Best skills (Discipline, Tumble)? Check.
Best skill is UMD imho. And other classes have tumble and discipline too. Especially in PRC.
Uber SR that is hardwired (can't be reduced even w/ Mord's D) into NWN? Check. Thanks, Bozo-ware!
SR is great, that's true. Still there are spells not allowing SR (usually require a touch attack though...). Anyway you have to stick to a monk to get this. Otherwise it is crap.
Max SR so high that only a few caster builds can bypass 100%? Check.
40 caster level is base. Monk can get 50 SR. Any straight epic caster can beat this SR. Any caster who takes no more than 4 levels of non-casting classes (practiced spellcaster). And there we have Archmage and Red Wizard, which one can use to bolster the caster level. And magic penetration feats. It is not that hard to achieve for straight mage build to get 100% chance to bypass that SR.
Multiple abilities that add to AC? Check.
Exactly two. Three, if you want to count tumble. Given that monks do not use shields (which can be as much as +3 from tower shield and +5/6 for the enhancement) and armors (+8 plate armor, enhancement is on robes), they need it. Or even non buffed wizards would hit them often. Also remember that it's not that easy to have both dexterity and wisdom high.
AC that a fighter needs a 20 to hit? Check.
So... Let's say mundane equipment (I mean no attack and AC bonuses on armor and weapon, which should even out). So 30 base AB, +2 epic weapon focus, +1 epic prowess. +14 str (18 base, +8 level ups,+12 str from items =38). It gives us 47 AB. Quite low honestly. AC of a monk would be 10 base, let's say he had 16 dex and 16 wis at the beginning. From stat increases he gets +4 AC. If he has both +12 wis and dex it's +12 to AC. 8 from tumble (nonexistent in PnP), 8 bonus AC for monk level. That is 10+6+4+12+16. It's 48. Then we should add the necklace, ring and boots. As long as the combined bonus is less than 19 hitting the monk is possible below 20. And this is not an AB-optimized build with 27 levels of Weapon Master or with Dragon Disciple and Bard for taunt and nice STR bonus. In a low magic world monks AC would be much lower by the way
Primary AC bonus type (Dodge) that stacks (while all other types don't?) Check.
Anybody is free to get AC boots... And again - he needs it.
Free level based AC bonus? Check.
It equals to a full plate at level 40. Much needed.
Free Improved Evasion to take 0 damage 95% of time to Evocation spells? Check.
Other classes have it too. And if you really optimize your DCs for spells it will be half damage quite often
And other classes get imp evasion too.
Free Deflect Arrows (95% change to avoid 1 missile / round)? Check.
Bows are in general weak in DnD. This is a nice ability, but the greatest damage is being done by magic and melee weapons.
Easy access to Epic Dodge (opp's first attack always misses)? Check.
Not that easy. You have to multiclass (in PnP multiclassing -> you can never be a monk again) either as a rogue or shadow dancer (maybe some PRC classes would help here). Which screws up your AC bonus, makes you get some abilities later and destroys your precious SR.
Free Imp K-down to always K-down mages? Check.
Fighter has 11 bonus feats before level 20. There IS a place for improved knockdown. Anyway, try to hit a full-buffed mage. You really can't do it without rolling 20.
Free disease / poison immunity? Check.
Who cares about disease and poison? Those are just little annoyances really... Nice to have, but nothing gamebreaking.
Free 50% concealment? Check.
Strong, partially countered by blind-fight.
Fastest movement in the game? Check.
Yeah, needed so he could run from his enemies ;P
Uber-items tailor made for class (Boots of uber Dodge, Gauntlets of uber damage)? Check
Take a level of rogue or bard (or many other classes from PRC), get UMD, use all monk-only items as you please. Problem solved.
If you can't be hit by spells (SR too high), take damage from spells (Imp Evasion) or even be hit by fighter weapons (AC too high), it pretty much compromises your whole system.
And you can't do enough hurt to anyone because your AB is so low and your damage is weak...
That didn't quite happen, but some WotC / Bozo-ware eggheads tried REAL hard to turn D&D into Monks & Punks (everyone else).
Monk is IMO only strong as a dip. 2 levels to get +3 to all saves and wis to AC as shapechanging druid or armorless cleric. Four levels to optimize the BAB. Well, access to monk stuff is nice too.