Beijing, which is also a metropolis,is a good choice. Here are some reasons.
There are enough metro lines and varios stations.
There are different scenes. For example, in the morning peak time, many commuters will go to urban area from the suburbs by subway.
Good color scheme!
If there is a shortcoming, maybe there is no wide rivers in Beijing.
But we have another choice, Nanjing.
The Yangtze river meanders through this city, which is challenging for players.