Needs better FX
I found that you really captured the feel of the original, but at the same time, I didn't feel like (at least on the intro) you really added that much depth to the song. It's more or less the same thing with different instrumentation. What this needed was some sort of beat, and maybe a good pad and deep strings to really make it FEEL like you were adding to what the original brought to the table.
Overall though, it's pretty well mastered. The only real comment I would make is that the Choir sample you used doesn't have enough release (resonance). You might also have tried using an echo effect. Same goes for that music-box-ish synth you used in the intro.