M22s with a sub are great for music.

JC is right though, that's a pretty suboptimal room. Even for 2ch music it's got issues, let alone placement for rears.

It's shaped very similar to my mom's family room but with different and much more intrusive fireplace placement.

Is the TV too big to go to the right of the fireplace to provide some balance there (and better viewing angle)? Probably. I actually like the stand it's on a lot but off on the far side like that it seems like kind of an afterthought.

What's your main seating position for TV viewing? For music listening?

I wonder if you'd be better off just putting stereo speakers on either side of the fireplace and sitting on the couch for music, not worrying about HT at all.