Consider Flexible Positioning
My room is smaller, but similar in use to yours, but my speakers are at the dining end of the room.
I have my heavy speakers on 3 wheels, so I can readily move them. Three wheels because more weight per wheel than 4, and 3 wheels don't wobble, put them anywhere, they find stability..
1. out several feet from side and rear wall, normal toe in for best imaging for single centered listener, speakers aimed directly at centered listening chair
2. same location, but alter toe-in for two listeners, maintain inside front corner, rotate left front corner to aim left speaker at right chair; right speaker aimed at left chair. Produces decent l/r sound, some sense of space and imaging; far better than hearing ’your side predominantly’.
3. pushed back into the corners, because the leaves are in the dining table for a large group. They sound darn good, and you are not concentrating on imaging or playing loudly so too much bass is not an issue.
My chairs are all ’transparent’ backs, the center ones rotate 180 degrees, to either listen to music or watch video.
see photos here