That is an extremely narrow room. Personally, I would get the best pair of speakers I could, and throw the rest at acoustic treatments. JMO.
How many feet will you be from the front wall?
If sidewalls are left untreated with a stereo system, the best sounding speakers will be those with the best off-axis response, as the reflections will be much more similar to polar response. Offaxis is something Ascends are good at, so if you don't mind, may I ask why you crossed them off the list?