I have the 3500 Passenger van (standard wheelbase); One common trend you hear in this forum is "it's better to get more than less"... I went from a 1500 van to a 3500 van and it made a HUGE difference (both had the 6.xL engine);
The 3500 tows much better, it feels more stable and the brakes are far superior.
The van feels like it works less and has much more reserve when you need it (like going up a hill);
Fuel mileage stayed about the same (11mpg)
I sold my 5,500 lb camper last year and bought a 3,500 toy hauler; Sometimes it's hard to tell that I have the TT connected.
I would recommend a 3500 over a 2500
Gerry