I think the vocals add a lot to the piece. The riff at :27 sounds mechanical and even mundane in a way, but I think the bizarre percussion at :42 adds a lot of energy to the piece. It progresses pretty slowly, but has a cool mood to it. I think the hi-hat is a little too loud throughout, but that's a tiny detail. The melodies at around 1:30 really start taking the piece in a new direction, which I love. At the same time, though, they make the piece sound really different from the first part. I like how you tried to bring it full circle at 2:45 by bringing back some of the more pizzicato-esque instruments. The reverb also adds a lot to the piece throughout. Another tiny detail: the ending cuts off suddenly. Still, I think this is really cool and unique piece overall. I applaud you for going with a more organic sound design here. Beautiful work! Keep it up, man. ;D
Please contact me if you would like to use this in a project. We can discuss the details.