You might want to consider Mutants and Masterminds, which fits your stated desires pretty well.
While it is primarily a super hero game. Its effects-based point-buy system is really easy to put down as a skeleton under any sort of skin that you want. I've played a Star Wars game and an Eberron game with the Mutants and masterminds system. Both were equally awesome.
In general, prep is pretty quick and easy. For your run of the mill mooks, use either the wide variety of stat-block in the back or make your own in just a few minutes. Basically, you choose the power-level of the NPC. And that number determines his bonuses to saves, skills, attacks, and so on. You can customize by varying up the effects and whatnot, but basically that is all it takes. You can, of course, flesh out your NPCs just like PCs. That takes considerably more time.
You really only need the one book, though Ultimate Power is a mighty hand addition that goes pretty in-depth about power creation.
The action point rules for M&M are excellent. Lending a very cinematic feel to the game. Even for non M&M games, I'd highly recommend looking at the M&M action point rules (called Hero Points).
The system is streamlined out of the d20 rule-set, so there is plenty of tactical fiddly-ness. It is streamlined, though. So... Streamier. Or whatever.
Later
silver
