Cool game! I think this is the first one that I played with boats and water. The visuals are great, good choice on the colors!
I noticed you are using the default Skybox provided by Unity. If you're up for it, I recommend you checkout this article on how to create a really beautiful and unique skybox: https://medium.com/@jannik_boysen/procedural-skybox-shader-137f6b0cb77c
Good luck!