QCC- I like this piece, but I'd recommend getting some better samples. I think you're using Garritan but something like East West would give you a much fuller, more vibrant sound. I believe East West would also work with Finale and Sibelius, but I'm not completely sure on this.
Not sure what your budget is like but check out this deal:
Complete Composers Collection :: Bundles :: Sounds Online
This is 7 East West packages bundled in one package for $1075. Sure, it sounds like alot of money, but the samples are more than worth it. After all, this would give you over 130 GIGs of high quality, multi-timbre samples! Also considering these packages can cost $400-500 a piece easily, this is a GREAT deal. I think using samples like this would give your music a better delivery, especially since several of the brass and string passages have a very MIDI sound to it. The music itself, is good though!
Also be very careful of your mixing. Some of the brass stabs peaked out, and this could be easily prevented. I'd also consider carefully mixing the entire piece to attain maximum performance. After all, any great piece of music can be inhibited by poor or non-focused mixing and audio production. I know that you're mainly a composer, but when you work as a composer in the digital realm, you have to take one many roles as an audio producer as well. At least, in my experience that has been the case and it has helped me greatly.
Hope that helps,
Nathan
PS- No I don't work for East West or profit at all by plugging their software!
I'm just a fan and user of their products.