It's a good beat honestly, but the track like you said is very empty. Listening to this by itself is extremely repetitive and boring. As it stands, it just doesn't have much substance. It's a great hip hop track, but just not very interesting to listen to you know...
If you want it as a standalone track you need to make some serious changes to it, either that or find someone to put some vocals alongside the beat.
Nothing much else to say. I can hear where you changed elements of the beat all the way to the end, but they just aren't very substantial or interesting to listen to by itself. I mean the dubstep wob wob bass is cool, just a little bit late lol. Keep up the good work though, good luck finding someone to fill the gap.
Please contact me if you would like to use this in a project. We can discuss the details.