I have looked at the Broncos, too, and like them a lot. Used to own one of the old Broncos back in the day, and had a lot of fun with it.
However, for various reasons, I like our current Jeep Wrangler much better, especially when it comes to flat towing.
As already indicated, only the bigger, heavier Broncos are flat towable, the small Bronco sport is not. Heavier means, pushing closer to the 5k hitch limit of the Motorhome, and closer to the 26k GCWR limit of the motorhome. Jeep is a good bit lighter than a Bronco, making it better for flat towing. Easier for the Motorhome to tow it.
Also, as already indicated, the Bronco transmission, transfer case is almost all electronically controlled, very complicated. And, has not been on the market long, hard to know how reliable it will be long term. Jeeps OTOH, have been flat towable and people been flat towing them for a very, very, very looooong time, with no real issues. I prefer Jeep's proven, simple shift lever operated transfer case over the high tech, untested electronically controlled unit the Bronco has.
And, to sum it all up...A Jeep....is a Jeep, and there's nothing else quite like it. Not much else to say, Jeep owners know what I mean. :) They've been around forever, and are just cool, have their own character, and are a lot of fun to own and drive. The Broncos are cool, too, and they do cost less, but they just....aren't a Jeep.
My vote....Keep the Jeep, at least until the Broncos have been around a few more years and have had some time to prove themselves.