Speaker set up for more than 1 person

You could also make the two guests sit closer together by putting one seat dead centered between the speakers and two chairs close together behind that centered chair.

I have a love seat with the left seat in the sweet spot. The right hand seat is for my dogs... but if there are two visitors they get the love seat and can switch back and forth. I sit off to the side.

I have never tried to expand the sweet spot, since that is so carefully set up. The width of a sweet spot is speaker dependent. 

Listening in the near field won’t really work as you’ve already found.  I’d move the listening chair(s) back four feet or more if possible and toe the speakers in only as much as you need to get a good center image — just experiment but this should help. 

I would buy a big cardboard, cut a small hole in the middle, about  20" diameter and put it where you sit normally. Whoever's head and however many can fit in the hole will be in the sweetspot. 

I wrote this specifically for more than one listener, both 2 channel stereo music and 2/5.1 video with several people on a sofa

https://www.audiogon.com/systems/11516