Help with Speaker Change

HELP! I would like to upgrade my speakers.
Please check my system and evaluate the room and placement I am forced to live with.
I enjoyed the sound of B&W 802Ds at the dealer, however I can't help but think they are too big for the room. Likewise for the SF Cremona M floorstander. I'm considering the B&W Signature Diamonds for their small footprint and similar sound to the 802Ds.
I've also listened to and enjoyed Wilson Duettes but worry it's not enough speaker for the room.
Perhaps with the WatchDog center/sub?
Would Sophias work?

Floorstanding or standmounts?

Any and all advice appreciated.

By the way the ceiling is 18'.

My Mythos ST/STS setup is very
good for movies, and I thought very good for 2 channel music.....until I heard the above mentioned speakers.