I say put it in the 70's or early 90's... either way stick to making games based off of the past. It not only adds a new level of reality, it adds real music.
I think there should be better graphics... and more realistic civilains. I mean, no kids? Well, shooting kids is bad... just give a three star rating automatically if a kid is killed. There should be WAY more models... I mean 500+ different looks. They can have the same clothes based off of styles, but different faces and body sizes.