Front speaker placement, trying wider placement.

Part of it is the compromises you are willing to make. Most of us want the best possible sound as system owner. So widening the sweet spot will reduce the sweetness of the spot. Having a reflectiveness of a flat screen will confuse the imaging. While the equilateral triangle is a rule of thumb, my experience is that optimal sound is achieved about there. Unless, you are running some odd kind of speakers like Ohm Walsh.

Sweet spot size?  Interesting.

anyone ever measure it?  Would you share with a significant other if only 2 feet wide?

all about dispersion.  Need to get some twine and build a twine enclose sweet area.  Will there be a shareable space?  
Many seem to buy only one chair for listening area.  Are spouses welcome to a listening session?  

Keep out of the corner, or the speaker in the corner will seem louder compared to other if not in a corner. 
 I placed large pillows behind the corner speaker, helped a lot! Took the boom and “louder effect” out.  
   12 feet apart, toed in a bit, 15 feet to my listening position on couch.  Works great for me. Large vaulted ceiling room. 
 Sure my Vega D-9’s sound and fill the room a lot more, but my small-med size towers sound so much better.

Check out Acoustic Fields. He just posted a new YTV that you should find very helpful
https://www.youtube.com/watch?v=f7RRIlFPE1Q

The wider stance moves you forward in the venue and makes the listening position more critical. Moving your head just an inch will corrupt the image. You also dramatically decrease the volume or power at the listening position as it drops off at the cube of the distance. The B+Ws are not directional so you need absorption on both the side and front walls as well as the ceiling or you will be missing detail and again corrupt the image.