Recommendations for balancing gain in bi-amp setup

I've been trying to calibrate my setup where I have
PS PWD Dac-> Joules Electra LA150 MKII pre -> Celestion 6000 crossover (treble, mids)-> Ampzilla 2000 MKII -> Celestion sl600 monitor ; Celestion 6000 crossover (bass) -> Mccormick DNA 500 ->Celestion 6000 subs.

The Celestion 6000 is a monitor/sub configuration and requires bi-amping. Both the monitor and sub have low sensitivity, ~84db and power handling up to 100W@8ohm. These are hard speakers to drive but I felt my Ampzilla and Mccormick combo should be up to the task.

My challenge right now is that even though the Mccormick DNA 500 which I'm using to drive the bass is rated at 500w@8ohm output and the Ampzilla is rated at 300W@8ohm. I'm still finding the bass playback from this setup is light and thin
or put it another way that the highs/mids are too bright.

My theory for now is that this may be due to the different sensitivity of the amps and I'm trying to avoid throwing another component in the mix like a equalizer to sync this.

Would like recommendations from anyone who has face such gain/sensitivity challenges before when bi-amping.

Gerald