Having collected/converted/created several thousand monsters, one thing I'd love to see is a more exhaustive abilities section that lists out the commonly used abilities.
For example, how many times have you seen the text for evasion, uncanny dodge, sneak attack, ability drain, all-around vision, etc. repeated in near-entirety in a monster or prestige class writeup? Wouldn't it be nice to simply be able to stick evasion on the SQ line and be done with it, much like scent or darkvision nowadays?