This is pretty solid start. I gotta agree with all the comments above. I like the drums and synth a lot, they have a nice sound quality to em' and the snare does a great job blurring the line between a synth and sampled sounding snare... The bass/808 is obviously the part to mess with more. It sounds a little too overdriven, not sure if that's the sample/sound you're working with or if it's a product of the mixing phase. If you're having trouble finding the right 808's to use (which can be difficult to find the perfect one) it might be worth looking at a couple 808 sample packs rather then trying to fix the problem in the mixing phase. Just something to consider, I'm not sure of what your workflow was for this one.
Anyways, it's a good start and I think everything except the 808 sounds solid. Good stuff!