A couple of things stand out to me in your mix. First is the acoustic guitar. It is very up front. Being that dominant presents that chopped figure in the first few measures of the phrase which does not do the song any good. Placing the acoustic more in context with the piano would help hide this unfortunate recording issue without doing any damage to the song. The other is the compression settings on the mastering. without a doubt this is an extremely dynamic arrangement and difficult to contend with. I think the release time on the compressor may be a tad fast as you can hear it release at times then grab back. I do like your drum room and think it fits very well in the context of the song.
