[*]Their fists aren't enchantable.
This I totally buy. Being 5 points behind on attacks 'cause of your BAB sucks, but being 10 points behind on attacks because you can't enchant your fists makes you a non-fighter.
[*]Melee classes with low BAB aren't viable.
This I totally don't buy. Druids disprove this with authority, and simple math tells you that there's a definite breakpoint when a BAB of +15/+15/+15/+10/+5 does as well or better than a BAB of +20/+15/+10/+5, provided each character has access to similar other bonuses (see previous point).
[*]The monk's class features don't help it kick ass.
I'm unsure of this. They obviously don't help it directly, but survivability is a big part of kicking ass, and while I believe they might have overvalued immunity to poison, immunity to disease, a bonus vs. mind-effects, minor self-healing, and Spell Resistance, I'm not sure how much.
It's obvious, however, that the Monk's inherent "offensive" abilities -- Ki Strike and Quivering Palm -- are *way* overvalued (especially if we're going to let them enchant their hands now).
[*]Monks don't get enough HP to be frontliners.
Again, Druids disprove this with authority. It's obvious that, with proper other abilities, a d8 HD is more than enough to make you a survivable frontliner.
[*]Becoming an Outsider as a pinnacle ability sucks this guy's butt -->
Duh.
So...assuming we
[*]allow the Monk's fists to be enchanted (and totally take Ki Strike out of the equation)
[*]up the DC of Quivering Palm to 10+1/2 character level+Wisdom and allow it to be used once per five class levels per day
[*]make the Spell Resistance based on character rather than class level, and
[*]grant the Monk some kind of Body Hardening Zenjoriki crap that gives him a point of DR every four levels and a point of Natural Armor every five...
What else does a Monk need to not suck?
How does this question and answer change if you switch things over to 3.5?