Mixing!
It's too loud. I think the blend of instruments could be better, the bend in the piano sounds a bit out of place. Other than that, I could pick out the tunes from the original fairly well.
But the mixing really REALLY lets you down. The brass in the bass doesn't bring out the melody real brass does, and it's too low and gritty, and because of that, it doesn't have the warmth and excitement you hear in a real orchestral song, or in a classical piece done by maestrorage or davidorr. To produce a song like live and learn, and to get it sounding good takes a ton of hard work and dedication, and a bit more experience helps too. I think you're tackling some stuff that's a bit too big for you at the moment, but it's good to see you plug away at it anyway.
Keep up the solid work, knux!
You'll get there in the end.