Thanks for the feedback, all! Your comments are very useful!
I used Xsample strings (a bit old but still great), SAM solo horn, Westgate woodwinds layered with Xsample woodwinds, the piano and mallets are from PMI orchestral instruments.
The piece will probably finally have 3 of 4 movements, depending on their length. I've written most of this in one night, except for the last theme at 3:01.
I agree it's somewhat static. I could alter some parts to create variations. The horn should be softer at 0:24 indeed. I'll be revising the structure of it, and I think I'll alter some transitions between the themes. Some crescendos could bring in more dynamics...so that would be a good idea as well.