FWIW, when we switched over to a 2007 Yukon XL Denali, it was crazy. We actually towed a 32' ultralight camper with it and our previous 03 Suburban. That 6.0L has 417ftlbs of torque and the length and weight made that 5500lb trailer seem like it's not even there.
I might suggest the same as you're looking at the Durango. The only downside is the 6.0L's including mine have a lifter knock on cold start up which is just annoying, but has no bearing on longevity. Ours has 155k on it now, and looks brand new.
I think you're on the right track, I just didn't think it's a good idea to sacrifice much camping comfort for saving 50lbs. At least, I wouldn't.
