By "real", I'm guessing you mean believably detailed. No, that they're not. What I mean is that the designs don't all need to be changed. They're "alien" buildings, for all practical purposes...they're allowed to not completely follow Earthbound design logic. In most cases, simply re-drawing the same content with more clarity and detail will be enough...it doesn't need to be a different design than what's there. No point in creating extra work where there doesn't need to be.

And, in a related vein, they don't all need to be redrawn to be crystal clear. Leaving some of them blurry also has a logic to it - atmospheric haze. The place is called CLOUD City, not SKY City.