Cool. My only suggestion is to vary the heights of the buildings a little bit...will look a little boring if they're all the same height. Also, adding some greebles to the tops of the buildings might be cool. Finally, this looks more like a business park than a downtown area. If you throw in some nice landscaping I think it'd complete that look. If you did, then you could make the area beyond the part you're detailing into a carpet of buildings to give some background. Just some thoughts.
M