FYI this is a prototype , it needs quite some development effort until it will be playable. I estimate this could happen in 2021 (but depends on too many factors, so probably even later), and the new engine with OpenGL 4.x might be required.
This is an engine thing that should be applicable to any map. One issue I do not know/thought is underwater ground texturing.
Multiple cool effect could be possible (sinks, sources, displacements, etc.).
Regarding performance, currently I think rendering is the most time consuming and that should be solved with tesselation from OpenGL 4.x (new engine). Water flow adjustments probably could be done in a separate thread and updated only occasionally (bonus ZK will use more threads), but I will not look at optimizations until I feel I know the answer to more complex problems (testing all unit types, pathing, buildings, weapons).
As a bonus, here is a video with units that are now swept away by the flowing water:
PS: thanks for all the enthusiasm, helps to know people like this!