I had a similar issue. My listening room is 16' wide by 33' long. It is an "A" frame with 12:12 pitch and no truss cross members. each end of the "A" frame is all glass. The floors are Oak Hardwood and the ceiling is Cedar planks. We have a large masonry fire place in the middle centered in the 16' width of the room about 2/3 back from the front wall where the speakers sit. Yes, a very reflective room, but a very good listening room. we treated the front windows with horizontal accordion blinds, the floor has a large wool rug and we have some large fabric paintings on walls. I also included a Schiit Loki Max, started with everything neutral and dialed down just a bit of the top end. Room sounds fantastic. I'm currently designing a kitchen addition and new listening room but it will be similar to the current one, simply adding the room to the end of the "A" frame but a bit wider with more non- glass corners for behind the speakers. Try the blinds, they fold away nicely so you can enjoy your views when you want to.
