Three things can help.
First, your choice in amplification is not helping. Those Classe Class D amps were not known for their warmth. if you want to stay with Class D, move to something like AGD and it will improve the situation. I know Classe and B&W were sister companies and voiced together, etc… but I had one of those amps here and I think you might benefit from a switch. Naim is a better match for Focal than Classe ever was for B&W IMO.
Second, with Focal, over toeing the speakers can help. Instead of having the toeing right at you, have it toed so the sweet spot would be about 3’ in front of you. This will help with Sopra and Kanta and might solve your problem.
Third, dampen your room. Over damping will deaden the treble. Curtains, tapestries, etc….
The best alternatives for a more natural sound while not losing anything in terms of detail and image in this price tier, check out Perlisten. The S7t towers. Despite beryllium tweeters, they are not even a little bright. Another alternative is the Wilson Benesch Precision series. I had a customer move from Focal Electras to Wilson Benesch P3.0s and they solved his brightness issue and he said they are better in every way.
full disclosure, I am a dealer for all of these brands except B&W and Classe.

