Who has interesting ideas for a new FPS?

Mine would be something like this: a game where you can pick to either play as an Angel or Devil, and from there you would blast through 'x' # of levels, trying to defeat hordes of the enemy. In the case you were an angel, this would mean fighting demons and hell hounds and such, and as a devil, you would be assaulting the Pearly Gates, singing angel wings w/ your unholy fireballs.

You would be able to use evil/good powers as well as various weapons distinct to either character. The devil could have a flaming trident for a melee weapon, for instance. Maybe the angel would be able to toss his halo like a boomerang.

It could be called "Heaven and Hell" or something. (copyright 2003 lol)

Anyone care to expand on this idea? or maybe post your own unique vision (not that mine is that 'unique') ?