Thank you all for your quick responses! I was hoping my newbie math and rationale was correctish enough. I have been pouring over threads off and on for several months.
I'm thinking most folks don't have to worry so much about payload because they don't pile six people into the tow vehicle. What had me concerned is that the weight of my family over the next several years will increase substantially, and if I'm at or near my max tow vehicle payload already, might as well start looking for a 3500 now.
My estimated tongue weight is probably a bit high but the 32TSBH we're getting is heavy, and has a thermal package and second AC unit...more weight...
I pulled my tow vehicle specs from:
http://www.media.chrysler.com/dcxms/assets/specs/2006DodgeRamMegaCabSpecs.pdf
I think the max payload of the 2500 diesel is surprisingly low because of the weight of the motor. Fortunately I got a good deal (not great but good) on the 2006 2500, mileage is at 64,000. I've checked on prices of the 2006 3500s out there of the same trim and I think I may be able to trade straight up for one that has a few more miles on it, maybe 90-100k miles.
Here's my plan: Throw the WD hitch that I ordered into the back of the truck, fill her with fuel and family and weigh her. Have the RV dealership determine the trailer's actual tongue weight as is. And get back to you guys.
Since we ordered the travel trailer and love the floor plan and amenities, will buy it and use our current tow vehicle but travel light(er) and local (maybe use a second vehicle) until I find a 3500 that I can trade out.
Two more questions:
1) Was the 1500 WD hitch the better option over the 1000 (ordered a Blue Ox Sway Pro)?
2) Are the tires that come on these new travel trailers, especially on a really heavy one like this, reliable or are there immediate upgrade options that I should consider?