That space is but 20.5' long? I also wonder about a 180 degree room flip like airscapes suggests.
Why not buy some acoustically transparent screen fabric, and install in your screen's frame? That's the best money you will might spend in the room as it will allow you to bring the
center channel up. And if there is additional room length, then you could hide the HVAC drop, by the AT screen wall.
My AT screen wall hides a lot of issues, in an even smaller, more challenged space. I gave up length, and did a 59" deep AT space, to visually clean up the front of the room (and let me host
2 big subs).
My next room won't even have a traditional screen set up. Plans are to simply lace in some AT fabric and use some velvet covered boards to hide the lacing and create the edges of the screen.
That is all based on the current masking system embedded in the minimal framing of the AT wall. I plan to eliminate the lower mask and simply have a sliding upper panel, to create a constant
width masking system. A bit of work but it'll be cheaper then any commercial screen.
That is a challenging space but I think a little bit of flexibility and some creative construction is something that could yield a nice looking room.