Quick riff to test new mix - any advice?

Man, the drums and bass sound killer in the mix. Guitars are a little muddy to me but otherwise pretty stellar sounding.
 
Yeah, I used a few samples that were knocking around this forum in place of the ones that came with LeafDrums, and there are three seperate aux channels for parallel compression on the kick, the snare, and all of the toms as a group to give the whole kit a bit more punch. My guitar tone changes approximately every third time I record - if anyone's got any suggestions for improving it, I'm all ears! The tone on NI Guitar Rig is a Lead 800 amp with a Screamer distortion pedal before it, going through two 4x12 60s tall cabs, one with an off-axis SM57 in front of it, the other with an on-axis MD421 in front of it.