The mastering is off...
The quality of the instruments is very variable in the piece. The strings sound okay, but the piano sounds very... I think MIDI is the only way to describe it. There's also no variation in the song, it just repeats exactly the same thing. Which is fine, to an extent, but, in my opinion, remixes should attempt to bring out the essence of the music, and thus use instruments and volume to, in this case, really get across the idea of an ebb-and-flow style, to reflect the turning of the windmill. This seems more... flat.
I know I'm not making much sense here, and it is my personal opinion, but I think this could be a lot better if some more work went into it.