Running M60s, the XO @ 120 and you say the bass output is weak? What frame of reference are you coming from? What was your old system like, could be you were used to boomy bass and not the tighter more accurate bass you have now.

I would also suggest running the sub hotter(higher volume level) than what the YPAO set it up at, add a few more db to it. The auto setups tend to run the subs lower than most of us want them at. Also move the XO back to 80hz and try it.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70