Nice article on Seating and Screen Resolution:
Just how much detail can you see and from what distance?
A bit dated, but this S&V article gives some good advice on how much detail you can see from distances
based on different resolutions/sources. Looks like a fine planning tool, IMHO. I'm 12ft from 96in. 16x9 Diag DIY screen.
Was thinking about 720 or 1080p, but I'm amazed at how good IN72 native image is here from HD/BR source.