The reason I ask is simple, me and some friends are actually working on making a game, and we're trying to get feel for what people would want a game like to to play. Basically, three simple conditions for a game like this...
...It has to be about eliminating targets
...It has to have a mission-based structure
...It has to be in a relatively modern setting
How would you make it? What gameplay features would it have? What would you try to avoid?