Two pages back the OP was convinced a pop-up was the way to go so I'll focus on that. If you are camping relatively close, the second vehicle idea might be good. The Town & Country was meant to tow a pop-up, not TT, but you still have cargo issues and your kids will just get heavier. If you have a second vehicle to haul a couple kids and at least part of the gear it might work, especially for shorter trips. I wouldn't take a long trip or mountain trip with it.
As your kids get older, you'll find that you can get the pop-up setup pretty quickly. My kids know the checklist and everyone has a station. We're set up in 15 minutes for a site that was level and maybe 10 minutes more if not. Our popup is older and the door is contrary if not level.