We always loaded the backhoe forwards, so that the rear bucket could sit on the beavertail and not hit any bridges. That's the way I prefer to load anything, other than a skid-steer may not climb the ramps forward. More to do with experience and comfort than anything else. I'd rather back off a ramp on the way off than back off the side of the trailer on the way on.
As far as a 3rd ramp, for the length needed for the trailer he's talking about, and the weight of his tractor, a piece of 2x12 with a piece of angle iron bolted under one end would suffice. A 4 to 6 foot piece can be had at Menard's for a few bucks.