To the OP - yes, you'll want to spring for the van over the Traverse UNLESS (as has already been pointed out) your trailer + cargo (want to emphasize that payload capacity of 3500 lbs on most vans includes people&luggage) puts you near that 3500lb limit.
If you're towing an ultralite and/or reasonably small popup, you'll be fine with a minivan (but please get a trans cooler & 7 pin trailer harness installed). But if you must tow and your payload is over that 3500 lb mark (or you're going to be doing a lot of hills in the summer), then you'll need to seek a different vehicle.
Question for the group, is there a specific year/brand of minivan that is particularly frugal? I know that the Sienna and Odyssey are very popular, but haven't found much info online of which model years have important features pop up etc.
In the context of the current market, the late '00's Sienna and Odyssey models are your best bet. I don't know as much about the Sienna powertrain, but the engine in the 3rd Gen Odyssey is the same that was used for the better part of 15 years across a wide range of Honda models. The transmission in the earlier Gen3's can be a little iffy, but if you can snag an 09/10 Odyssey with less than 150k on the clock, you'll get an easy 100k out of it (provided you keep up with maintenance).
Next best bet is the 4th Gen Odyssey (what I have), or the up until recently phased out generation of the Sienna. You can get away with an older Pacifica or a 2015+ T&C/Grand Caravan but just be prepared for lower build quality and some more service needed sooner.