What started out as an optimistic and adventurous piece of music was turned into elevator music by the piano melody. If I were you, i would seriously consider amending the piano so that it matches the feel of the supporting instruments. The strings in it gave me the sense of it building, and that was ruined - i hesitate to use the word, by the piano. So, i liked the feel of it initially, a lot, but the piano fell very short for me.
Also, the sci-fi sounding Tss noise was out of place for me. More than anything, it felt like filler put in to make up for the lack of time spent on properly rounding out the music.
Then again, this is all me, if you like it, more power to you