I ran MMGs for a while in a room that size with excellent results. It sounds like you have a dedicated room which is key and actually gives you better options than a larger shared space.
I would (did) run them in the nearfield with a sub well away from the room boundaries. You will get a wide an craaaazy deep soundstage with good imaging and tone. Plus nearfield will take your almost square (bad) room mostly out of the equation. I am thinking speakers 3-4 for apart and you the same distance away. Keep speakers pulled well into the room.
I think you would be in for a real treat.
I would (did) run them in the nearfield with a sub well away from the room boundaries. You will get a wide an craaaazy deep soundstage with good imaging and tone. Plus nearfield will take your almost square (bad) room mostly out of the equation. I am thinking speakers 3-4 for apart and you the same distance away. Keep speakers pulled well into the room.
I think you would be in for a real treat.