Yeah the 'burb has been passed by, by the towing world. We had one for years and traveled all over the west but only pulled lightweight popups and later a travelmanor. You need a HD truck like a 3/4 ton. The Crew cabs will give you plenty of room for the kids in the back. And you'll have a lot of storage space in the bed of the truck especially if you get a topper or tonneu cover.
You are braver than I, in taking those small kids camping....LOL. We took ours to all 48 lower states and Canada and Mexico. But we let them get a bit older and they were spaced farther apart. That took quite a few years of course taking 3 to 4 week vacations.