My analysis of your montage:
Firstly, you need smooths instead of sped up clips of nothing. Smooths = third person views showing a kill, showing where people are running, etc. etc. Use smooths to transition from one set of kills to the next. Yours ended right as another began, with no transition time in between. Even if you fade to black and then back, that's better than instantly starting a new clip.
Secondly, you should sync the kills to the music better. You kind of started it, but it didn't really continue.
My only other complaint is in your overlay abuse at the start. I didn't like it at all.
Overall, the clip gets an 6/10 from me. Things to work on vary from cropping out unneeded time-wasters, adding smooths, and syncing your kills. Good luck!