That room did turn out awesome.

I would flip the 180 to see if the angled side on the bottom works better this should throw the center sound more upward and not directly out.

DTS runs the sound effects hot, have him try DD as well just to see if that helps.

Does your Brother run the PB 13 in 20hz mode? I have mine tuned to 15hz(1 port plugged) and it is great to have that extra little bit of rumble.

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