I agree with Sydian that it makes sense that the latter half of the game is mostly on water, but I don't like it :c
I hate Surfing and needing Dive and Waterfall to navigate through the game. I do like a lot of the Water-types available in RSE though (Swampert, Gorebyss, Milotic, etc.) but it's easily my least favorite part of the game, aside from running in a giant circle around the map to get through the first five gyms. That doesn't make training very efficient, especially if your battery dies and Trainer Check doesn't work.