As the old world i will try to reproduce the urban environment that surround me now 
(9, 12 and 16 floors typical houses from "soviet times"). To recreate i have more than enough info (maps - can try to follow all distances for nice perspective; + technical drawings from realestate sites).
To make the typical building more live i can play with different windows, balkons, air conditioning and other details that make buildings look very chaotic and... "messy but live".
NO lights in windows. But the houses are not ruined and not so old as in Prypjat (Chernobyl).
The new world above: some references, but still not decided. Hope that will be something procedural and more clean as design 
for contrast to the old world. Maybe some signs of military actions from people. But the question of the hostility / friendliness of "aliens/strangers" have to remain open.
