It's a fun game but I just didn't feel as involved as the SimCity series (prior to the latest, which was a disaster).
I feel like C:S seems shallow to people because the first and only real challenge in the game is traffic. Most of the elements that are challenging in Sim City actually do exist in C:S, but the game is tuned such that you have enough money to buy your way out of any problem.
Sim City games force you to make many difficult decisions because your funds are so limited. I hope that in the future the C:S developers make note of this, and they take the time to tune their games to replicate that challenge.