What I'd do would be an animation in a style similar to this one (you might have already seen it):
http://www.dailymotion.com/video/x1wygv_iraq-animation
It's basically a series of well done drawings. The camera moves from one spot to another and all things come alive, they seem to move even though they're mostly static. I think it's realtively easy to do (it's certainly easier to do than a full blown 3D movie) and it wouldnt consume a huge amount of time to get it done.
Oh and if there's no chance for a simple but good looking intro then I'd suggest having no intro at all 
I think this is a great idea.
The drawings can be concept art, and should be relatively straight forward for somebody with a bit of stylistic ability to create. It would be reminiscent of the old UFO: Enemy Unknown intro - which is another positive.
I would avoid doing 3D stuff, it is much harder to pull off. Even in the 2D arena, I'd avoid things like animations (beyond very simple flashes or gun muzzles or movement indicators).
