Aesthetically I can totally see how a 2D visualization could look great. But then you end up with curved roads and buildings hiding other buildings and things become very confusing.

One interesting change (but it's a big one, at least aesthetically) would be to force a certain angle of view, rather than allow a complete pan-tilt. Something in a "total war" fashion, so to speak. Or - at least - allowing such camera to be used in the options.