Grave Rave
Well for drum n bass, I think you need more highs... your snare hits are good, the second hit that has significantlyless velocity seems a bit amissthough.
My main complain in my opinion, is your main synth. It doesn't sound eqed, and after 2:13 it pushes your sound out a bit. It's really grinding, I'd add some delay on it, and a flanger, really fuck that thing up. Maybe some bitcrusher, distortion, tube, tape, honestly the more fucked it is, generally the better it sounds and the less grinding :)
Your drum beats are effective. Just try some more hats and ride :)
With some work and production, this could be a really banging tune.