I looked at a number of Australian trailers used in the outback for inspirations for our teardrop trailer and incorporated a number of the ideas, i.e. all aluminum frame, solar, water filters...Our camping is a good bit more tame so it will not ford waste deep rivers...
One of the things to notice is the axles are independent and the center of gravity is low. Many of the off road trailers have an angled rear to give clearance rather than setting the trailer up high over the axles as you see with too many US made trailers.
http://www.kimberleykruiser.com/australian-off-road-caravan
http://www.bushtracker.com/