One day, a long time ago (erm, June 20th, 2010) I had this idea to double the damage bonus of weapon enhancements. I originally called this Enhancement Attuned, but when I went back to the idea, I renamed it Weapon Enhancement Specialization. Then I made two more feats, Enhancement Power Attack and Keen Enhancement.

Basically, I discovered that in all the homebrew I have looked at, I have not seen people use this awesome resource pool limited by wealth and a hard height limit (until epic). You can trade out enhancement points for other bonuses.

Now, when I did this, I was only thinking about weapons, but now I realize that I missed armors. So, I shall show my homebrew (I give you an unlimited non-revokable right to copy these feats, as long as you do not claim credit as the creator.) and ask for what you can create. I request that it be allowed to be placed on DnD-Wiki.org (you must give explicit permission if you want me to move it there, see link in signature)

Keen Enhancement [Fighter]
Trade enhancement bonus for increased critical range.
Benefit: When making an attack option, you may trade a multiple of +3 weapon enhancement bonus to increase the range of critical hits. Each +3 traded in this manner doubles the critical range of the weapon. This range increase does not stack with other critical hit range multipliers.
Special: This may be taken as a fighter bonus feat.

Enhancement Power Attack [Fighter]
Trade weapon enhancement bonus for increased base damage.
Prerequisites: Must have held a weapon with a minimum +2 enhancement bonus.
Benefit: At the beginning of an attack, you may choose to lower the enhancement bonus of the weapon to increase the base damage die of the weapon. Every +2 enhancement traded in this manner increases the damage die one step.
Example: Ryan, a human, picks up a +2 dagger. A bugbear then charges him. Since Ryan has Enhancment Power Attack, he trades the +2 enhancement bonus for increasing the damage. He makes his attack roll, so he rolls 1d4 + Str for the damage roll.
Normal: The enhancement bonus of a weapon gives a +1 on damage and attack rolls. Masterwork items have a +1 enhancement bonus, and magical bonuses (such as the "+3" in a +3 Greatsword) are enhancement bonuses.
Special: This is a fighter bonus feat.

Weapon Enhancement Specialization [Fighter]
Weapon enhancement damage increases in your hands.
Prerequisites: Must have held a magically enhanced weapon.
Benefit: Each point of enhancement of a weapon increases your damage roll by 2.
Normal: Each point of enhancement of a weapon increases your damage roll by 1.
Special: This is a fighter bonus feat.