I like it a lot. I agree with what the others said about bringing a little difference in the textures, but I disagree about the changing of color: for me, the uniform lightbrown hue of the whole city is fascinating, seem that it doesn't need any atmosphere to convey a vague sense of pollution and heaviness. So, these are only my 2c, of course, but I won't change the color at all and I'll stick with some minor tweaking of bump and frequency of the buildings' texs. S.