Some speakers of course will work better when up close to backwalls than others. I think there was even a thread some time ago regarding which are more suitable for that purpose. You might want to run a search?
I've always believed that it's preferred to fire into the shorter dimension of a rectangular room, dividing the wall into thirds as reasonably as is possible. My room is similar (18 x 12) and this arrangement works quite well despite the fact that speakers sit toed-in & within a foot of the backwall (by necessity) so I never even tried them when pulled well-out into the room. Fortunately my speakers happen to be one of those models that are designed to work near walls, so I still get decent staging (although I'm sure it would be better yet if I could pull the speakers out a few feet). Of course the sofa sits in the nearfield, but this arrangement sounds fine whether listening seated, or when further away in adjacent rooms.
The room is fairly live & I use no special acoustic treatments, although the whole ceiling is sprayed with 1" thick cellulose insulation fiber, which really helps knock down the slap-echo. Other than that, just have drapery, wall rugs, a large floor rug & stuffed furniture.
So your proposal seems reasonable enough, & I think that you'll be pleasantly surprised once you get it all tweaked in. Good luck!
I've always believed that it's preferred to fire into the shorter dimension of a rectangular room, dividing the wall into thirds as reasonably as is possible. My room is similar (18 x 12) and this arrangement works quite well despite the fact that speakers sit toed-in & within a foot of the backwall (by necessity) so I never even tried them when pulled well-out into the room. Fortunately my speakers happen to be one of those models that are designed to work near walls, so I still get decent staging (although I'm sure it would be better yet if I could pull the speakers out a few feet). Of course the sofa sits in the nearfield, but this arrangement sounds fine whether listening seated, or when further away in adjacent rooms.
The room is fairly live & I use no special acoustic treatments, although the whole ceiling is sprayed with 1" thick cellulose insulation fiber, which really helps knock down the slap-echo. Other than that, just have drapery, wall rugs, a large floor rug & stuffed furniture.
So your proposal seems reasonable enough, & I think that you'll be pleasantly surprised once you get it all tweaked in. Good luck!