I've been playing Evasion lately, and mine is sort of based on it.
I level with an enviroment much like it, but with many different paths, harder "takedowns" I've almost never been seen, even when using knifes only. By harder I mean more complex. You get to pick you're class before playing, but with only sniper rifles and handguns, the starting weapons are always supressed. "Random" enemy placements, and 4 or 5 mission objectives, kind of like Resistance 2's co-op.
Hey really that is a good idea, Spec Ops mixed with Resistance 2's co-op.