I would start looking for a different set of main speakers for added punch. Quite often the "punch" people are looking for is from the mains themselves and with the built in subs I suspect much of the punch is lost through the mains. Just remember your room and/or seating position could also be killing/missing that added punch you are looking for.

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