You need to focus on the fact that no matter how much optimizing or tweaking you do, a Monk is simply not great at straight-up combat. Monks are good at doing *crazy stuff*. Monks should not be slugging it out rolling boring attacks, they should be looking for non-standard actions.

A good monk will have lots of ranks in things like Jump and Tumble, and can use the environment to do unusual things both in and out of combat. Thus, try to engineer combat environments that have things to interact with, and encourage the Monk player to use them.

You can take this a step further by using concepts from more narrative games like Spirit of the Century, whereby you encourage the player to *suggest* the existence of interesting options. A player should be asking things like, "is there a chandelier I could swing off?", and your default answer should be "yes", unless there's a specific reason to say no.

Finally, give magic items which actually work with unusual combat techniques. That means: forget about boosting attack, AC, saves, etc, and focus on cool Wondrous Items that can be used creatively. Boots of Springing and Striding make their already good movement and Jump abilities even better, and if you give a Monk an Immovable Rod and they can't think of something interesting to do with it, then the player should not be playing a Monk.

Incidentally, Monk's best pure combat options are non-standard as well. A strong optimized Monk uses abilities like Trip, Grapple, and Use Magic Device (UMD is feasible for utility / buffs because the DC for wands is only 20 and you can retry fails without expending charges). They really don't need house ruled full BAB or armour or anything because they're *not Fighters* and shouldn't be played the same. 

For example, Trip is a Touch Attack, so you're a LOT less likely to miss against most targets. And since Monks get Improved Trip for free at level 6, you get a free attack to try to deal damage if the Trip succeeds, PLUS an AoO when they stand up. Add Enlarge Person for Size bonus and extra Strength, and Trip becomes way better than just attacking. Monks are better general-purpose Trippers than Fighters because a Fighter has to use a specific Trip-compatible weapon, whereas the Monk can just use their unarmed strikes.