Well, I had some extra time this weekend and I played around with my system a bit.
1. I took up Rene on the suggestion to arrange the speakers and my listening chair at the distances they would be in the new room. Things got a little better, but not incredibly so. If this remained my listening space, I would probably not move stuff around to do 'serious' listening. The benefits were negligible, but it was a worthwhile experience.
2. I drug some of the office furniture out, and moved the system into the proposed room. The soundstage was large and engaging. Deeper than the front wall of the room, and stretching the side walls. In this nearfield listening set-up, the soundstage was also incredibly engaging. The room seems to have great potential considering it was half emptied (although close to what I would have in there if it was a listening room) and no acoustical treatments yet.
I've updated my 'Room Layout?' thread with pictures of both spaces:
Room LayoutNow, to convince the wife. ;)