HD is built for bad roads! I would still not get the 3500#, or the HD--- we travel light
. The 2000# is taking the bounce rather than the frame. It is a well manufactured piece -- i would guess it is well engineered.
My original design was to reinforce the frame and get the 3-4in height w/ a welded section of tube. The trailer has good clearance. The tail could be worked (raise the bumper--add skid or do some cutting and fiberglassing) We have a truck that raises/lowers in the back 3.5in.
Truth is-- we like one step in-and-out the door!
The dimensions are on the Timbren site -- call them - they are helpful. its just that little bit longer on the frame that a beefed up system was necessary for the Trillium
4500 (the frame offsets). My opinion is the HD would be called for if bad roads were normal and heavy loads were common.
My theory the extra weight low and centered makes for the sweet ride so sometimes its just luck.
Longer spindle fat tires would be good for getting up a muddy creek, and matching spare. Fenders would be easy to add. But I am not sure fat equals better. My experience is mostly desert.
4X sites are great for creative solutions and they have installed trailer Timbrens with good results so check in w them.