[Rendar]

Why not have the ability to call shots to certain limbs whenever you do a basic attack. Minus hit, but effects based on it.

You sunder someones legs? -MOV/DODGE
Arms? -HIT/DMG
Head? +FP consumption/higher damage on hit.

Of course your hit would take a penalty, but attacking someones head and hurting it would cause their 10 FP skill to cost 15, and it would deal a lot more damage on said hit.

Arms being battered would cause you to lose the bonus of mainhand/offhand weapon/shield/nihilist depending on how much you did. Etc.