As far as game mechanics, have you seen the combat system in Hybrid Heaven? It's that kind of twist on conventional game play that will make for a memorable title.
If you're wanting to cater to the power user faction, look at different ways to go about it besides the ability to level a mountain with you pinky. Exceptional accuracy or dexterity can also make a power user. (ie. Every hit is a critical hit or you can deflect every attack directed at you (ala Neo in the Matrix))