I would like to suggest trying to make what sounds like it should be a bassline, an octave or two lower when it comes to the dubstep sound. It also sounds too loud. The kick drum is being drowned out, and I'm hearing this with my headphones on.
Make the bassline softer, bring the sub up a bit more. Also you need to cut some holes, either volume or filter, in the sub and bass for the kick drum to poke through. It wouldn't hurt to add a bit more click/beater noise to the kick drum, maybe by layering in a hi-hat.
Maybe raise the highs on the percussion, especially when the synth comes in. I'd also suggest tightening the kick a bit, not so much release.
The section from 0:31 to 1:01 is kind of long; maybe cut it in half.
The piano and the pad thing are a bit loud. Also the main synth sounds a bit too detuny to hold chords well.
Also the sub jumps in volume depending on pitch.
I like the panning on the hats, but you could actually afford to have them drift from side to side more.
For some reason the only thing that really gets me is the piano melody, which sounds a bit off possibly because there isn't much emphasis on the first note of the phrase. Making that one note a little bit louder and harder would do a lot for that section.
The kick kind of gets eaten by the low strings. Given the steadiness of the low strings, maybe you should try something other than a 4ttf beat, or at least more variance in the drumming.
Yeah, I find that to be kind of strange myself. I do plan on changing up the rhythm of the drums pattern later on. This all comes from the price of working on headphones. When it comes to the actual mixdown, that's when things should sound a lot better, minus the headphones.