Not sure I agree with some of the assumptions built in here - both to the survey and your stated question.
For example, there's almost no way I can respond to your survey that's accurate. Which combination of boxes should I select to indicate lift, A/T tires and factory AWD? In my case I've swapped factory AWD to 4WD, but I'm pretty sure that's not in the way you've implied with the survey - the stock front diff, axles, and suspension are unaffected.
I also question the assumption "even if they are FWD vans will be heavy and have a higher COG". My van has a GVWR about the same as a modern Colorado or Ranger (or a GMT800 1500 Silverado "contemporary" to when my van was built, before everything got huge). Converting from AWD to 4WD was weight neutral since no new parts were added, only swapped. To the point of COG, my load floor is well below the bed-height of the pickup, so the only stuff "up high" to raise the COG are two more pieces of glass vs. a crew-cab truck and a little steel for the roof. As someone who has cut a big chunk out of that roof, I can attest that stuff is THIN. I
I will admit, my COG is certainly higher than the average Astro van since I've got the GTRV pop-top up there, but I'd certainly compare my van's COG to a mildly lifted truck with a fiberglass topper.
That said, and getting back to your original question - with the sparse changes I've made to my van, it's pretty close to a "stock" 4WD pick-up from the early 2000s, except that I have a bigger enclosed space with seating and sleeping capacity for four people. To mimic your info:
2003 Chevrolet Astro Van with GTRV Pop-Top
6100lbs loaded with a family of three
Factory AWD converted to 4WD by swapping transfer case from S-10 Blazer
Re-geared axles and 4" lift to facilitate taller A/T Tires
16' long, 7'8" at the highest point (I'd have to remove the roof basket to fit into a standard 20' shipping container), nominal roof height ~7' (GTRV stands for Garageable-Top RV, after all)
I pick my routes based on that criteria. Without a winch or lockers, I'm not going to be rock-crawling with the buggies, but so far I've yet to meet a forest service road or desert wash that can stop us. I've deployed my TRED mats in silty sand once or twice, but usually nothing more than a shovel is needed. I have stacked rocks to smooth out a big step on a couple of occasions.
