I don't know the books but this actually sounds really cool! I'm definitely keeping my eye on this. Will there be more information if/when the OOC goes up? I'm wondering, for instance, how traction cities even came to exist and become a thing in the first place. Seems like too ambitious and advanced a project for a people that's been returned to a new technological dark age. Not to mention there will almost certainly be all kinds of little details-questions that come up sooner or later. A map would also be helpful; I realize it's based on Earth, but you did mention that some oceans have evaporated so the topography has probably changed significantly from what it is today.

As said though, this is absolutely interesting to me. Flavor-wise I'm probably leaning towards doing something water-oriented, maybe one of those floating cities you mentioned.