One thing that annoys me a bit about cities is that every improvement of the same type has synched animations. An example:

I've built 2 gardens. The little guy with the hatchet in the first garden will be perfectly synched with the guy in the other garden, lifting his hatchet and wiping the sweat off his forhead at the exact same time. Looks pretty robotic.

2 other suggestions for "non robotic" cities would be to randomly align improvements (you know, rotate it 90 degrees for example) to make the improvements look a bit different from each other, and also to have some kind of a cobblestone texture between improvements so that the city looks like one unit instead of a walled-in center and some small patches of stuff around it.

Just my two cents.

EDIT: I just wanted to add something that probably doesn't deserve its own topic, since it's most likely been mentioned before: Every other time I start the game, all 3D graphics are blurry. It happens exactly every second time I start the game, changing any graphics settings makes no difference at all.