Hmm i spend too much time trying to find out what to model in the scene.. it would be best if someones could come with buildings interiors concept arts.. then from there ill do my modeling/rendering part..
Do you have access to our shared dropbox folder? I have dozens various backgrounds there. We might even use some of them instead of rendering if it looks good enough.
As for the outside world i can make something really good but ill have to see if it blends with the girls im making i could do a map like you linked with different biospheres and as we add more places somewhere in the map..
Before we try it, we need to know exactly how good it will look and how much time will take. I suppose a map with dozens small details should be much harder to render than more or less similar girls bodies.
When I worked on the city map, I considered creating a more extensive maps of regions in the future.
I can tell you what could be improved. You used monochromatic, simple textures for ground surface. If you look at my example, ground textures are more complex there, thus more realistic. Grass is green there too, but there are places with lighter and darker grass.