I have also been using 5.1 for a long time. There is a very marginal change going to 7.2 or 9.2 or 11.2 or 13.2 and IMHO not worth the extra wiring/speakers/loss of WAF/etc. (WAF = Wife Acceptance Factor) Makes me think of razors. Now with 23 blades for an even closer shave. (after the 3rd blade more blades are teats on a boar) Next week someone brings out a 24 blade razor and it keeps going.
Yes, my wife is one who would gladly make do with the 79ยข speaker and thinks everything should work by pushing one button. I'm sure she wishes my two surround speakers were out of sight but she tolerates them. Still, she does seem to get a kick out of movies that make extensive use of the surrounds.
When I first got an SACD player, one of the first discs I bought was the Philadelphia Orchestra recording of Saint-Saens' Organ Symphony. My wife dearly loves that piece, and no traditional redbook CD has ever replicated the sound of the organ well (IMO). When the multichannel organ came thundering in at the end she actually had tears in her eyes.