Needs more metal.
Just kidding, but seriously. I'm itching to hear your metal make a comeback. For this, I should let it be known that dubstep is probably one of the genres I dislike (to put it lightly) the most, next to generic country. They all just sound the same to me. I probably liked the first dubstep song I heard, after that, I realized it was a dumb genre.
That said, like the other review said, you've created something unique with the sound of it. At least unique to me. The build up like that is focused starting with such a simple sound and building up to lots of energy. When the song kicks in at 0:45, normally what the beats that would bore me to death keep me entertained by the awesome melodies you've crafted over them. They honestly make the song for me. So you wouldn't be surprised that my favorite part is at 1:27 because it's just purely that. Then it goes on and adds that dubstep thing which keeps it from getting repetitive, which is ok.
Also, may be my earphones and speakers, but I think your sound and mix is great. Soothing as fuck. That's one thing you got nailed down so idk what that other was talking about. A suggestion, I do think it would be awesome if you make a metal version of this song. Part of what gets me through it is imaging some of the dubstep as rhythmic chugging sounds. I think the conversion would work great with some tweaking, and knowing your style when it comes to the metal you've shown, it would sound fantastic too.
SOrry for the long winded review, but yeah, you should know your sound is a success if you got someone who doesn't like dubstep praising your song.