Your options are wide open with that trailer. My favorite half ton is a 3.5 Ecoboost F150, so I'd encourage you to take a look at them. Plenty of power and because it's boosted you get a relaxed experience. You could get by with a midsize truck but I think you'd find a half ton more enjoyable over long distances. I'm generally not a fan of half tons if you're trying to haul a larger trailer and family around but in your situation a heavy duty truck would be overkill unless you're planning on up-sizing later. Just my two cents.