Suprised that someone hasn't come up with this yet, but here is my idea for a new feat.
IMPROVED ABILITY [General]
Through intense study and dedication, you have improved your ability scores.
Benefit: You may add a +1 inherent bonus to your intelligence, charisma or wisdom score. This bonus is cumulative with other inherent bonuses, but the total may not exceed +5 total. This feat may be taken more than one time and bonuses do stack.
Did not include Str/Con/Dex because it could be abused with abundance of feats fighters get -- but logically, I could see it happening.