You had to know I was going to comment on this...
As someone mentioned earlier, it all depends on your wife and what she wants to do. My wife likes being with me doing my guy things, but if it wasn't for me she probably wouldn't ride on her own. I respect that and like the fact she wants to be a part of what I like to do. She even wants to learn how to play golf. She rides with me on one or two trips a season. She really wants to go with me to Quebec and ride after we traveled there to check out the area in September last year. I don't see her ever wanting to be on her own sled. Again, every woman will be different. I bought her the very best gear to wear so she was always warm. She wears a tech vest from Diva's (she likes the bling on it) and hasn't been cold. I don't take her out below zero for obvious reasons, but has ridden in the low single digits and didn't get cold. I upgraded the rear handle warmers so I actually have to turn the heat down on some days. I used to ride on the back of a 2-up while teaching my son to ride and found the rear hand warmers didn't work very well stock. Now I use the 2up to ride with my wife and if I have a friend come up who doesn't have his own sled, they will use the 2up.
Now Pete, I know you can't be talking about me...we did 280 miles on that trip to L'Anse through the pipe line and pretty much kept up with you with my wife on the back of my sled!