Having owned a 1996 Chinook (21 footer) for seven years, I can say that I have never seen a small motorhome that was up to the same build quality as it was. I think that our PC is better built than most other small motorhomes built today, plus the fact that the factory will customize it for you puts it ahead of the others.
We went to the Intervec-Phoenix rally last month in Colorado Springs, and also spent a week in Estes Park, Colorado. We towed our Jeep Liberty, which is close in size and weight as your Wrangler. We just sold the Liberty and bought a 2015 Cherokee Trailhawk to tow behind us. We did see a couple from Texas that was towing a Cherokee Trailhawk behind a Ford E450 motorhome and they said they loved it and did not have any problems towing it. We did not have any problems with power except on US68 in Maryland. The going up the hills there did slow us down a little. Kermit (the owner of Phoenix) was there and fixed any small problems anyone had. On one side of me, the guy had a broken escape window that was replaced and on the other side the lady had a step that the pin had broken and was swing freely. It was fixed also. Both of them were fixed for free. I had the same broken step pin on the way to Estes Park. You can read about it on this forum. It cost me a $100 to have a mobile repairman come and fix it. I don't know of any other motorhome manufactures where the owner comes to their rally and fixes any problems.
Two six volt batteries do put out 12 volts but the run time (hours) is greater. You might find that the two 6v run longer than the three 12v you have now. Check the amp hours on each battery. This is why 6v are used on golf carts.
My wife thinks that our 2552 is the perfect size and layout for a motorhome while still allowing us to go just about any where. It comes down to one queen size bed vs two twins bed. The 2552 is really almost 28 feet long while the 2910 is 31 feet long. Either one will be a great choice.