Great textures
I really liked how you utilized the full orchestra, in that you didn't throw everything in all at once the whole piece. The piece has a great pulsing feel to it and the notes were placed exactly right. I love the fugal section at 1:18, and I'd be interested in seeing the score, if you wouldn't mind. Good use of unconventional mode at 0:14; is that Lydian you're using?
One criticism, though, is that the ending doesn't seem to work very well. I understand that the piece is just building the whole time, and I think a resolute ending would kill the piece. Instead, it seems like the ending should be the most intense and leading part of the piece. It would help if it were loud.