for the rock part:
add power chords/strumming, you can do this with ample metal hellrazer and add stereo processing so that they're full
add a heavy bassline and optionally a constant mute guitar, stuff like that is in zenology although triton is my go to for basses
you could also layer the kick with another one, but dont make it too heavy like a trap kick
fills are good though
for the drums, id alternate hat velocities because it sounds too repetitive and unrealistic right now
