Really like the overall atmosphere, and the transition at 1:17 is great. I also really like the melodic idea and its development. However, the second melody starting at 2:53 sounds a bit too "drunken" for my taste, some notes lag too much behind because of the glissando.
The only other thing that struck my ear as "off" on the first listen was the kick/knock percussion in the intro. The two hits in fast succession sounded a bit sloppy to me, maybe because of the machine-gun effect. I would maybe try lowpassing the first hit of each of those or just tuning down the volume, but that's just a random idea. Maybe it's good as it is.