The window spacing looks weird, especially on the buildings in the background. (Are those points of lights even supposed to be windows?)
General rules for window spacing:
- Buildings are divided into storeys/floors. These tend to be of a uniform size past the ground floor. Windows rarely cross over between storeys, so they tend to be aligned more horizontally than vertically.
- The bigger the building, the more of its surface is covered with windows.
- Floors will look smaller on buildings further away, but the decrease is gradual.
- The tallest building in the world has 163 floors. Don't go any higher than that if you want a realistic, present-day setting.
Also, I think you could strengthen the overall impression of the picture by darkening all colors except the yellow and adding a bit of blur around the yellow, like this:
(I cheated and used a filter for the blur.)