Thats a good idea, i got tunnel vision with the dream of having some big *** floorstanders...
I think bookshelves all around might make more sense, my dreams are crushed... haha
The Aperion's are damn good speakers and IMO have that same "warmth" and dynamics that you are seeking.
Not sure if the B5's wouldn't be too big for surrounds in a room that size though. Maybe go with the 4B's for now and then use them as surrounds when you upgrade the L/R's down the road. Trust me when I say they are amazing speakers especially for their size!
Also I wouldn't rule out towers as if you go Aperion they have
several tower sizes that may be perfect for your room.
I can't comment as to the Ascend's as I have never heard them but they do come highly recommended here.
You have a LOT of options for bookshelves if your budget is under $1K.
The
Budget Bookshelf Shootout would be a good place to start.