Hello, I tried out your game and I really enjoyed walking around listening to the piano and guitar music. I think mixing the music with the art is very powerful. Not sure what your plans are for the game, but I think it would be interesting to have some kind of puzzle to solve inside each one of the portals. The puzzles could tie into the theme and message of the game. I enjoyed reading all of the content on your website and feel like it could be a really interesting game if you were able to get more of those ideas into the game in some kind of interactive way. Not sure how to do that exactly, but I think it could be kewl.
Are you using Distance Field Ambient Occlusion? It looked like you might not be. If you enable it, I think it would add a lot of dimension to your trees.
Great project! Keep up the good work!