Research your payload, max trailer weight, and check the weight rating on your tires.
Don’t be so focused on “length” of trailer. You need to know what it weighs. A lot of trailer weight numbers are for the bare trailer, empty, no water tanks full, none of your stuff in there etc.
Also most travel trailer manufactures make just the frame and trailer and have other companies do the interiors so they don’t factor those weights in either.
I’m not a fan of towing a large family sized travel trailer with a half ton pick up. Guys do it all the time but most don’t know the capabilities of their truck and don’t understand what it’s doing to a light truck over lots of hauls.
When you step up to a larger truck that will be rated to haul a nice size travel trailer most guys focus on getting more “power” for hauling. What they really benefit from a 3/4 or 1 ton is the larger brakes, stiffer and more capable suspension, beefier frame and chassis on some models, better transmissions and differentials, better gearing and much stronger rear axles, better cooling systems, and motors like to be worked hard and run high miles. You also get tires that you know are rated for heavier weight hauling.