There is nothing wrong with a solidly constructed centre bar for the hitch as opposed to an a-frame.
Not just light weight army trailers... have a look at a 2.5T rated boat trailer sometime 
50mm Hitch Receiver at the rear is also good for a bike rack...
But if you have a compliant builder I would incorporate solid recover points to each rear corner of the rig.
Often when trailers are all messed up - you will be disconnecting and then cornerpulling for the win.
Steve
'95 130 dual cab fender (gone to a better universe)
'10 130 dual cab fender (getting to know it's neurons)
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