JJ’s approach is the only thing that makes any sense to me. Everything else feels over-thunk and meaningless.
In the real world, almost nobody ever sits in a “sweet spot” at home or in a theater. Every immersive system tries to create fixed sound source locations. It’s uncalibrated and meaningless in the home unless it’s only used for reverberation. In music, musical translation is king because that allows emotional communication. To this day, when I switch popular music to mono without saying what I did, most people and virtually all musicians will tell me that I improved the mix.