Last year (almost exactly) we picked up a 2012 F250 CCSB XL (base model) 6.2L gas with 102k on it, as I didn't feel like navigating the (expensive) mine field that appears to be modern diesel trucks. Shortly thereafter, upgraded the trailer from a 2013 Salem T21RB (24' OAL) to a 2018 Cougar 28RLSWE (~31' OAL) with a Husky CenterLine hitch.
Truck tows like a dream (compared to the '06 GMC 1500 we had before with the 24'). Mileage is down a fuzz; 8-9 is pretty average, 10+ on a good day on *flat* land - but there ain't much of that around here. Seems like every trip is uphill - both ways ;) MPG dips down into the 7s if trying to do 70+ mph thru hilly country. Did a couple short trips last summer, along with a two-week multi-state trip from central WA to MT, across ND to Bismark, back across and down thru SD into western NE, then up thru WY, MT and ID back to WA again. Earlier this year (February) made a run down to Phoenix and back.
For the most part, the truck drives smoother with the extra weight back there, and at first on the flat/straight-aways we kept checking the mirrors to make sure the trailer was still there!