I'm fine with keeping all the speakers stock and in your suggested positions, but getting an Atmos 7.1 AVR with some sort of room calibration microphone setup. Let the system deal with any tonal issues of the older Axiom v.2 speakers. Keep the M22 as a possible rear surround speaker or front height channel.

I prefer the TV to be at eye level when seated, but you can always tilt the screen downwards.

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