You lost me here. Sorry, what? No.
Here's my experience: I've only ever solo'd red side for obvious reasons, so all I've ever done are missions.
But the zones are all extremely similar to one another. There's no way you can refer to them as "Unique".
I don't know about enemy variety, but because the zones are so generic I don't really notice much variety in the dockworkers or builders or goldbrickers attacking me.
Internally, the offices are much MUCH more interesting (and yes I know it's just a skin-job) than the vanilla game had, but later missions blue-side had some good variety in them, too.