Diagonal set up in small room & floorstander

I apologize if this has been said over and over but after 4 years (call me Slowmoron...) of fighting with standing waves, room resonance modes and the rest of the usual junk in a 13*12 room, I decided to go diagonal early this week. It is UNBELIEVABLE the difference it makes, cleaner sound, much better soundstage almost going half circle around me and the bass quality is tighter than ever. I almost feel up to the challenge of trying to fit floor-standers in there but this may be asking too much. Any suggestions for FL that would work well diagonal in such a small almost square room?
It will make a huge difference. I had to do the same thing. The only problem is that there isn't a lot of information around about placement diagonally. So, you have to do a lot of experimenting, but like you I felt the difference it made was very unbeleivable.

I hear that's what speaker designers do at shows when they have small hotel rooms. It should work equally on floorstanders.
Something that doesn't respond all the way to 20Hz. Demo some floorstanders that respond to 35-40Hz on paper allong with a pair of bookshelf speakers that respond to 40Hz. A good floorstander should respond evenly down to this range without getting into the super low frequencys. There are some quality bookshelf speakers that are remarkably close to full range. I don't know what your pre/amp combo is but the Spendor S6 or S8 comes to mind.

Good luck!