If you like the concept of going off-road with a travel trailer, you might be interested in the features of some of these Australian caravans (such as the
Kedron in this video) which could be applied to a moulded
fiberglass trailer.
Nerf bars
U-Haul fans may recognize the body-protecting bars around the lower edge of the forward part of the body.
Suspension
The Kedron caravan featured in the video appears to use the
Cruisemaster independent suspension system with leaf springs and shock absorbers.
Coupling
I'm not sure of the specific type, but it looks like this caravan is towed with a high-articulation off-road coupling, instead of a common ball and socket coupler.
It also has
dual spare tires,
wide tires, and
high ground clearance.