I agree... I believe I could be happy with a 92" screen. I have a room about your size (a little narrower, but longer) and I sit about 11' back for a 97" screen. Very large for me.
A 92" screen is only 80" wide... see the
screen calculator... It takes a few seconds to load the calculator.
106" is 93" wide. You would need skinny speakers to fit on each side appropriately.