FWIW - I have a small asymmetrical room (3.5 x 3.5 m) - bay window on left , angled doorway on right . I sit near the back wall like you.
The best thing I ever did was to change out my larger ported speakers for small sealed monitor type speakers (Harbeth P3s in my case) complimented with a small SVS sub.
Gave me more flexibility in positioning and they image really well .
The right speaker had a wildly different measured response below 250Hz due to asymmetry - very little output at the listening position due to cancellations - I ended up moving the speakers 1.2m into the room to get the right speaker to better fill in around this region.
The speakers are toed in 45 degrees , equilateral triangle arrangement with 1.9m sides, but I could go closer and still get good driver integration.
Being designed for mid/near field listening you can get pretty close (1.5m or less ) and still get a well integrated sound . I imagine this would work less well with the bigger quad towers. So one option is smaller boxes and pull them into the room
(angled in so you can’t see the sides) when needed - keep the space around them clear.
I’ve been in your position - it’s a real pain when space is limited. But my lesson was get smaller speakers ! Probably not what you want to hear (sorry
)