This looks quite promising!
Indeed there is need for more work on the visuals but you already have incorporated too many elements in this game to keep me interested...
I guess the sky is a sky dome, correct? It's probably better to use a skycube instead of a sphere (imho, is a more flexible way to change day/night conditions and provide better visual impressions).
Also, baked textures on the buildings is the way to go (shoot some buildings with their shadows on them and make the textures out of these photos).
But, as I said, it's looking promising. Keep it up, dear neighbour.
