So I must be really missing the importance of this to the game play. Besides building a damn and watching the water adjust to the damn, how does this enhance the the challenge of the city simulation?
Every feature you've listed could be turned into the same formula:
Beside [insert feature], how does it enhance the challange of city simulation?
You somehow think, that since [water simulation] is added, [your suggestions] aren't added as a result. Completely wrong.
A guy was employed to do the water dynamics because the developers wanted it in the game. Developers then focused on the actual simulation.
In fact, if anything, all the suggestions you listed would perhaps maybe hurt the developement of all the more essential simulation aspects, such as transport, day-to-day citizent simulation, because your suggestins would actually have to be addressed by the developers and as a result, they would have less time for more important aspects.