Great job. I think you need to change the first instrument used as the melody though, it sounds too bland. The instrument at 0:21 sounded great, but was a little too quiet. The switchover at 0:49 seemed a little delayed. at 1:20 got too quiet too fast. The melody at 1:34 delayed a little and was disorientating. The switchovers at 2:00 and 2:19 were disorientating as well because the melody seemed to be getting a little random. The problem with the switchover at 2:19 is that everything got quiet just before the new melody started. What you want is the background to drift over the quiet and into the new melody a little bit.
Good luck with your next piece of music!