GM is finally getting away from the 10,000lb GVWR for it's new 2020 3/4 tons. So if you are worried about the stickers and staying under it, the 2020's will be out soon and either the 2500 or 3500 will have you under the numbers.
Myself, I believe the 2,500 and 3,500 are just an upper overload leaf different from one another. I hear this is mainly to keep people from paying higher registration and fees in certain states.
I just recently went form a 32' travel trailer to a 2020 High Country 331RL a few months back. I have towed it on four trips so far and absolutely love it! Hooked up my 2015 Silverado 2500hd 4x4 Duramax squats a bit as expected, but I am still level and not lower in the rear of the truck at all. With that said, I do use lower stableloads from Forklift. They actually sent me a set for free to try when I had a 1/2 ton Chevy. Never installed them until I got the 3/4 ton. I loved the added stability they offered when towing the travel trailer and again activated them with the new fifth wheel. It gives me a much more controlled feel! Wouldn't tow without them now.
My truck rides and feels great! I have not plans to upgrade anytime soon, though I am getting pretty excited about the new GM HD twins as I hear more about them!
Good luck and safe towing!