Small room = small speakers
Big room = big speakers
A 12 x 11 room with big floor standers is a miss match. Plus you listen at "fairly low volume" levels so there's no need for adding bigger/more. All speakers have a level of volume they require in order to sound good and those floor standers won't get to the proper level.
A good pair of stand mount Sonas Faber Sonetto II G2 on stands would be a far better choice IMHO. I would also add a small REL subwoofer for adjustability.. This would fill the room of that size.