a few things -
any issues with the REQ from your AVR? which one?
Do you use REW and any outboard eq like some flavor of a minidsp, thinking subs here- got any?
got a map of your layout, dimensions, stuff like that . . where you sit, separation, toe-in, when mentioning just L/R ,
also, your usage of the system music vs movies
If the HTM 12's can be had, do it.
My F15's just pour out a wondrous clear detailed HUGE sound field , that 15" SEOS horn , some very beautiful work . .
fussing with dialing things in- priceless
from talking to
a while back,
the HTM12's ( and maybe the HT12's)
using the same front baffle but making the cab 18" deep can lower the tuning
and maybe with some other EQ get to be close to full range into mid/ upper 40's.
setting F15's and F12's to "small" to enable BM seems like a crime . . .
as for the drivers, CDS's - way better minds with the right stuff got it right, put their names on it and own it .