Okay I'm going to start this off broad.
When you're editing to a song of that intensity you really need to be able to match it. Good over-audio editing has a flawless flow. Dubstep has so many hits that it's important to keep up. Quick cuts is the easiest way to start. When I say quick, I mean it. The point is, keep up with the music you choose when making an edit like this, otherwise it gets really boring really quickly. Which brings me to my next point.
Only use the best shots and cut down! This applies to almost everything, short and sweet leaves the audience craving more and brands you as someone who makes the audience want more, aka a good filmmaker. When your audience stops watching half way through because they got bored that doesn't leave a good lasting impression of your work on them. Be quick, decisive and assertive in your editing.
Skip the iMovie (or whatever intermediate editing software your using) title presets. Trust me, you can make something better, try. Cut down on the length and number of titles as well.
That's my standpoint from a broad perspective. Keep on doing it though! You've got a good start.