Background:
Having grown up with a '95 GMC Safari and having gone on tons of travel-trailer camping trips with mom and dad, I set out to buy a van so that I could do the same with my family. I'm extremely disappointed that mid sized vans today don't even mention towing capacities (apparently because vans aren't meant to tow anymore), but managed to talk my wife into buying a 2005 Astro. The problem? We don't have a trailer yet, and now that we have two kids and a third on the way, my wife is fed up with the single rear door and wants a different van. Buying a second van is not practical, and I'd hate to give up my Astro for something dinky; buying a travel trailer is still a goal, but my need for four is threatening that goal.
My questions:
1) Has anyone ever added a driver-side rear door? I've looked far and wide, and my searches have found nothing but instructions on replacing the 3 doors already there. I'm afraid of what this means for my Astro, and so in one last desperate attempt, I'm hoping someone out there can help me. I assume structure of the vehicle is an issue, as well as placement of the gas door, but if I can even install a tiny slither of a door just big enough to throw a kid threw and reach my arms in, I might just save my van.
2) Does anyone have any other suggestion? Custom 3-seat lazy-susan seat swivel? 90 degree swinging bench seats? Basically if my wife has to crawl in the back, it's not going to work for her (especially as child 3 gets bigger and bigger in her belly). If I could find a way to enable her to put three kids in their car seats without getting in the back, I might dodge the need for the fourth door. (In anticipation of "Put the kids in for her," I should say that 3 days out of the week, she has to take our kids to preschool and doctor appointments while I'm at work. And I've already tried telling her preschool and doctors are for schmucks, but she's not buying it.)
3) If it comes to it (wincing as I type this

Thank you in advance!