I had a thought about this issue today as I was driving past some serious water issues and a thought occurred to me. Smaller bodies of water appear to render correctly (or near correctly) in the client. Could the issue be related to the number of geonodes or the area covered by the body of water? If so, perhaps a way to deal with this would be to get editors to reduce the size of these places which will also result in fewer geonodes. This will in turn should reduce the processing required for rendering.
Just some crazy talk perhaps, but the community's thoughts (and developers) would be appreciated.
If some testing is required, I have plenty of issues in Vancouver, BC which we can play with...
Samsung Galaxy SIII, waze version 3.9.5
AM - Vancouver, BC and surrounding cities
Waze Beta Tester (Android)