The part that comes in at :16 doesn't fit in too well because of whatever scale it's on.
I love the part that comes in at :47. Awesome, sounds great.
The part at 1:30 is REALLY out of place. It could fit in if you built up to it, by some tense percussion (and maybe a minor key), and a sudden pause, beforehand, but otherwise, it seems awkward. Even with the aforementioned changes, it might still end up sounding like a complete change of genre, so it may be better if you were to cut that part out. It's nothing against the instrumentation- just the dissonance doesn't fit well with the melody.
I'd vamp up the percussion in a few parts as well. It's kinda repetitive, rather boring. You can keep it the way it is for the most part, but add in some brief variation, for example, at places like 2:10 or 0:50 (you did this technique really well at 1:34).
What I like most about this song, perhaps, is the rhythm. The part that comes in at :35, for example, provides a good layer to fit in with the melody.
However, you could work on dynamics quite a bit. Subtle, slow, periodic changes back and forth between loud and soft could work well for the background rhythms. Additionally, the percussion section could use a nice accent/louder sections now and then (perhaps at like 1:36) to catch the listener off guard.
Anyways, nice job on this piece. Like theMacATTack5 said, this could easily be a great song; it just could use some minor changes here and there.