Family of 9 here, we had to give up tent camping as well due to a medical issue. I don't miss setting up our big tent that we affectionately called the circus tent.
The two vehicle option would work for you if you weren't planning any long road trips for the foreseeable future. We take some pretty long road trips so this option would not work well for us.
I would take a second look at the vans. We have had two Chevy Express 3500's and they have been great vehicles for us. Ignore the fact that it is a van. When you see your kids spread out in the back and plenty of room for all of your gear, you will change your mind. Your kids can actually have a few friends come for the weekend. Plus our new Duramax diesel van gets 20 mpg when not towing. We tow roughly 9500 lbs behind our TT and don't have any issues.
Whatever vehicle you decide, make sure it has the heavy duty trailering package on it. This has some features like a transmission cooler that you need and are expensive to add on. Good luck with your search and have a lot of fun looking.