Well by all means
I can't really classify this as being professional, from a theoretical standpoint your lacking in overall orchestration and voice against voice contrapuntal motion. you have certain voices doing things that wouldn't really be necessarily strong for the role that it plays within a full orchestra environment...
don't get me wrong its a wonderful arrangement and by all means provides that buzz that you get from hearing one of your favorite pieces.
you have to make sure than when you state a certain chord that you follow through with that chord by making sure that you add all chord members when needed and nothing more. like in the lower voices of the piece you are emphasizing and completely different chord with a single note and it creates this awkward dissonance that makes me feel rather uncomfortable. when you have an instrument solo you have to make sure that no other instruments are interfering with its direction (i.e poor melodic support , improper harmonization, and vocal conversation between the solo and the backup instrument)
honestly i would say that this would make a stronger case if it were of a different genre. but thats only because certain parts reflect pure orchestral scoring and most other times not so much.
i apologize if i seem harsh or abrasive, I just cannot send your way with a pat on the back. haha! i just noticed that you were concerned about being professional. with that information i have to provide something that way you can get to your goal of being pro (i'm not saying that my way is the only way or the best cause its not by all means) i just wanted to plant a little seed of contemplation and you have my full support as a veiwer. Great work ^_^
what program did you use to get that sound quality?