Are planar speakers less prone to room interaction

Thanks all for your fantastic and detailed responses.

Jwpstayman: It's more the asymmetry that is disturbing to the ear. Immediately to the left of the listener's location you have the windows, whereas to the right you have the empty space where the room doglegs into the kitchen. That leads to a really annoying image instability - as a singer goes up and down their range they will move from side to side. I'm assuming this problem is caused by the windows, though there's other things that could be a factor (the exposed ductwork on the left and not on the right; the chaise of the leather couch). I'll definitely look into the Marigo dots - hopefully they will mitigate the problem somewhat (the double cell blinds on the windows now don't do much).

Duke: That's incredible detail, thanks. It never would have occurred to me how quickly the drop-off in perceived volume would differ as you moved around the large room. I'm not sure I can afford a full-range electrostat but the larger Maggies can be found around $1000 which seems like a feasible replacement for my PSB Image T45's.

Thanks for the interesting ideas. I like the idea of the Maggie 1.6's, though my main concern is that I can only move them out 3.5 feet or so from the wall. Hopefully that would be enough.

One thing I like about the Maggies is that there are matching centers and surrounds avaiable, and my system is about 70/30 home theater / music.

Those are very interesting suggestions, Ngjockey. The Newform Research stuff looks like it would be in my price range and reminds me of the Lineaums that I used to have. The only problem with them is that they didn't fill the cavernous room, which is why they were replaced with the more robust PSB's.