i kind of feel like the synth screams over the rest of the track so its hard to actually focus on the rest of the tracks and all you hear is the synth, in addition i believe you should change it up as it is with you the entire song and gets slightly (i'm sorry to put it this way) boring by the end... if you mix it up it would greatly improve the musical value of the track, i had the same problem when i started 7 years ago and learned after many mistakes that it is vital to the livelyhood of the track that the synth is varied so listeners don't get bored. Also, i would invest in some good audio editing software i use Audacity which isn't that great but it still gets the job done and its free http://audacity.sourceforge.net/ its virus free, take the editing software and just touch up the ending so that it doesn't just cut off. I hope i'm not being overly critical and that this has helped just a little bit.

I give my opinion, don't worry.
In music, you have two ways.
The first is to build in such a way a short melody which can be used as the ground, like in rap or Hip hop. It's something which is closed to trance state.
The second is to build, not a melody from a block, but from an idea of evolution during the 2, 3 or 4 minutes of the song.
In your case, if I were you (I apologize, but I feel immediatly what I could do), I rewrite the partition, the piano melody to build a line of a story (as the ones you can listen in Chopin, Beethoven, SuperTramp, The Doors, etc). So that, you transform completely the rendering of your music which becomes a "composition".
It's my opinion, but if you work your piano line, you can render a beautiful music (an other one).