My understanding is that they're going to add a new three-row Jeep, resurrecting the Grand Wagoneer nameplate for it. It will be considerably more expensive than the Grand Cherokee, which isn't cheap. It won't be available until some time in 2017, perhaps spring, as a 2018 model.
The Durango is a very nice vehicle for what it costs, Auto writers tend to prefer how it drives to any other SUV in its price range. The reliability of the new electronics added for 2014 have been iffy, with bugs continuing into the 2015 model year. I hope Chrysler gets these sorted out soon, as they're the only thing that keeps me from recommending the Durango and the Grand Cherokee.
I'm not a fan of the Tahoe because its third row and cargo area are not practical.
The other remaining true midsize SUV is the Toyota 4Runner. I don't like the ride or the handling, and there's not much legroom in the third row, but they're very reliable.
You might also try the Toyota Highlander. Though car-based, it has a truckier character than most such vehicles, and it rides and handles better than the 4Runner. Towing capacity is up to 5,000 lbs., so with the towing package it should be fine for that twice a year.