Hmmm
It has potential. One think I noticed is that there is very little (if any) dynamics in this piece. It sort of just "dies on the vine" after about a minute or so. Add some dynamic contrast, expecially at moments when the melody jumps more than a third (I think heard a few in there). You could also try introducing new instruments to carry the melody. This will add more color and interest to the theme. The same string patch playing the same thing gets old fast. I also noticed that you stayed in the same key and roughly had the same chord progression for the entire piece. Add some accidentals! Make the listener questiont their ears for a second and either reward them or punish them for it (whatever is your taste). Your melody seems to wander a little bit too much as well. For the most part, it has a reletivly standard stepwise movement with occasional interval jumps. I guess all I can say is be a little mroe ambitous with it. Add some dissonance. Add more intruments. Add some dynamics! With a little work this could be great!
Good luck!