Your situation is similar to ours. I had to convince my wife to give up the Yukon as a daily driver and go the the 2500 HD. It didn't take long for her to love driving the truck. You can do much more with a truck. We put a roll up tonneau cover so she could still put stuff in the bed and not get wet or fly out. As others have said, for a daily driver there really is no difference between a 2500 and 3500, but you would see a difference between a 6' bed and 8' bed. I wish I had the 8' bed as you can haul more and it is better for heavier loads.
On the bunk house part, we have a bunk house. There are lots of options these days. I just saw a new design that has the rear bunk with a queen bed on the bottom and a loft. Looked like a great design, even a rear 1/2 bath. Would sure help with teenagers. I have a friend that went with a front living room because the couches opened up to a bigger bed than the typical bunk house and their son is very tall, couldn't fit in a kid bed. That is one reason we have looked at Toy Haulers. We don't really have toys but the rear area could be a great bed room for a couple rowdy boys. However, TH's are very heavy up front especially without toys. You would need a DRW for that. At least for one with a rear garage that is closed off.
Good Luck, looks like you have a lot of advice on this forum.