Interesting that you mentioned the Apogee Stages.
My room was a little bigger, but I had them on the long wall (just 18 inches from it) with only 8-feet between me and the speakers, so it was pretty nearfield. I never heard them boom, and I have had several other speakers boom in this room badly. My intuition tells me I would really give the Stages a try w/o fear because of your room size. They are a historically important speakers that convey a sense of reality in a very unique and satisfying, non fatiguing way I never heard elsewhere. I think they are flexible to place and worth the try. They are cheap used, so it's not that big a risk, and they don't need expensive amps to sound great (I had an Aragon 8008 when I had them back in the mid 1990s.)
The stages are different than other planars, and I don't think the same installation rules apply. To my ears, I never really liked Martin Logans, Maggies, Innersounds, or other panels, but the Stages were pretty awesome while I had them.
(Mine developed a buzz in one woofer and I moved on to dynamic speakers, but I still miss them.) I would give'em a try if you are starting from scratch and considering them, and not worry too much about your room.