My suggestion would be a Chevrolet/GMC Suburban/Yukon XL with the 6.0 Liter and 4.10 gears. In addition, I would suggest staying with a two-wheel-drive model with locking rear differential. During the past 15 years, I have had two GM products with four-wheel-drive and my current will be the last - - - it just is not worth the cost in upkeep (my current Suburban needs an electronic control board every 15,000 miles at a minimum cost of $750, and now it needs a rebuilt transfer case at a cost of nearly $2,000 at 200,000 miles).
The Suburban provides all of the comfort and convenience of the family stationwagon in the only form that can be found today with the capability to tow almost any Airstream trailer built. I find that I can carry everything that I need for Airstreaming behind the third seat, and it take very minimal preparation to be able to carry seven passengers in comfort. Unlike the pickup, it is a rare day when I can't reach something in the cargo area either from the rear liftgate or from the third seat - - one of the reasons that I disliked my pickup was the continual crawling into the bed to retrieve objects that had shifted to the front completely out of reach.
Good luck with your investigation!
The setup doesn't appear to be level because the site was actually on a slight slope and the tongue jack had been lowered to bring the coach into level for a one-night in-transit stop.