Perhaps level designers simply aren't needed at this point and when they are, things could progress quickly. They already said that cities will be virtually the same, right? (Or is that speculation?) I think it would be reasonable to launch with a basic city template and then plan on rapid additions within the first 3 months of the game. That leaves more dev attention on more important parts of the game.
The Secret War turned out to be fairly cartoonish, no ammo. Seemed very theme park. ie follow the yellow brick road and don't put much thought into it.