nicely put together piece.
I was looking at this for awhile and I and I like the composition. I was immediately attracted to the structure on the left then my eyes slowly drifted across the piece. I'm guessing you know a thing or two about color theory, there's a good balance between warm and neutral colors. I don't know much about color theory but I would add something. (keep this in mind, this only my preference.) I would add a little more complementary colors on some the buildings or objects, of course that may not be the style you were going for or maybe I'm missing something.
I'd also like to add that this reminds me of some concept art, this one specifically.