I watched your video, inferno. Excellent work! I can't wait to see this when you're artwork is finished! Looks like a fun game, to say the least!
For the FPS vs. 3PS debate:
I think FPS is best for games that focus primarily on shooting, guns, and military simulations.
Games that have a lot of fighting, hand to hand combat, melee attacks, and more arcade style games (like GTA) are best in 3P.
P.S.- Your laser guided rockets are awesome!