umm... i could do it quite quickly actually... once you have a pipeline for your art assets for gs then your set, setting up such a terrain would be just a few hours in photoshop and a very handy shader that we use, same goes for the other models, few minutes to handle texture and shaders... the water is quite easy also, ofcourse it'd take some planning to make the scene still look good, good models alone wont do it...

i often thought of doing a similar scene but then reality bitch slapped me and i knew that it would just be another scene that wont be featured and only get a few comments, then no matter how breathtaking it MIGHT look, fade out of existence.. if someone really needs to see such quality then lookup hummels wavefield...

so i didnt bother and probably never will.. any scene i work on will be from my game, senseless making another demo

and yes, a new member of gs probably couldnt do that as fast as a new member to unity, that much i knw is true...

as said, with 3dgs its never a question of IF it can be done, the question is HOW to do it and by WHEN