I think the problem with most mini vans like caravans, is there built off a car platform, and there kinda scant for camping space. The Astros are built on a truck based platform and are boxy, they have enough room, more actually, to easily do a Westfalia type conversion and available suspension's or upgrades to handle the extra weight.
I've seen a couple/few members at the astrosafari web site take their vans to coloradocampervan
Custom Van Conversions For Camping, Work, and Play He has happy customers.