Grading and adding some post light effects to evaluate proof of concept...

 

Here I was just testing light techniques and 1 single pass composition. As you can see, even with an anime look, toon render doesn´t look convincing because of the many shading levels. Anime are recognized as single (or at least) 2 levels of shades only.

This is a concept frame to show compositing and all possible situations to recreate land + sea.