I think you've nearly got it.
Here's how to make it better:
If you like this kind of Dubstep, put more growls in it. If you're DAW doesn't let you do that, download some from www.looperman.com
The drop was weak. To make this better, add more bass (as I just said), and use WHITE NOISE to make the sound fuller. If you don't know what white noise is, try this:
https://www.youtube.com/watch?v=BzujrStf_TE (if that one doesn't help there are tons of videos out there)
That's about it.
Could you check out my music? That would be awesome!