Something post-post-apocalypse, cause it's a criminally underutilised genre/setting, IMO. Sure, playing the struggles of humanity clawing its way out of the ashes of the old world has its fun moments, but therein lies the question of "and then what?"

Equally interesting to me is what kind of world lies in store once the dust (eventually) settles. I.e. When the descendants of the survivors move on from picking through the bones of old world cities, to having reestablished some semblance of a functioning civilisation.

Ergo, give us something like Fallout 2 or New Vegas, where we can see some semblance of civilisation returning, rather than the "scavenger world" aesthetics and themes of Fallout 3.