Some things to work on...
First off, take a listen to Stravinsky's symphonies of wind instruments and octet, I think you'd like the style.
As far as the composition goes, the pace seems slightly plodding to me. It could use some rhythmic variety. The fact that everything seems to move in quarter notes and the bass keeps a steady pace makes the whole piece lack surprise.
The instrumentation leaves you no bass instrument; you might want to use a bassoon instead of an oboe or a bass clarinet instead of the clarinet so that you'll be able to write with some more depth.
I'm assuming that the harmonic style is supposed to be "modern". The harmonies sound slightly off, but that's fine as long as it is intentional. Typically, such harmonic variety should be matched by rhythmic variety as well.
As far as production value is concerned, it is going to be very difficult to get a slow piece to sound good without investing an equal or greater time into *production and performance*. This is one of the hardest things to learn. As we write our piece, and hear the computer playing it back, we tend to hear *what's in our head* instead of *what's actually playing*. Your sample library can definitely be pushed to a new level by using dynamics and volume expression. Having crescendos and decrescendos on sustained notes is going to be the key to making this sound real instead of synthesized.
Let me know if you have any questions or if you want me to take another listen. I hope this is helpful rather than harsh. Thanks for posting this, and don't get discouraged.
Thanks for your review. Full of good constructive criticism.