I've tried again with PSSM shadows but it's impossible to get them working. The frame-rate is <10 FPS even testing on a high-end pc, and it doesn't give good results. Changing the theme of the level now would probably require to change lots of things.

About shorelines, they are dynamic together with sea.

I will put three different graphics quality options, and also a walktrough mode.

Don't worry about movement or animations, I think they are smooth and good-looking.