And interesting idea that in the end is not really playable.
Rivers typically do not have shore waves, but that is a small nit compared to what happens when you actually play this map.
You guessed it, it's a nightmare of arrow ships and shore towers, total chaos. Archers versus arrow ships, villagers sitting ducks, fishing boats doomed from the start. The snaking rivers turn the game into some kind of bizare ships versus land unit battle and there is no room to build. Not really a practical map to play unfortunately. There is a reason why the original nomad does not have rivers...