The payload in the Dodge 2500 is an impressive 3000 lbs or so and you get the new coil springs or possibly rear air suspension. The 3500 has (I think) about 600lbs more payload but it comes at the cost of going back to bumpy leaf springs. A 2500 is well within limits of what you need. Duallys and even 3500SRW are mainly just needed when you get into 5th wheels.
Take a 10000# TT - even at the maximum assumed tongue weight of 15% you still have roughly 1500# of room for people and gear in the truck to stay under the GVRW of a 2500.