Sometimes the old ways are the best. It's basically been downhill since the Bowlus. Airstream/Silver Streak/Avion are symmetrical; while the Bowlus has a blunt nose and a long boattail. With the door at the hitch, it has slick sides.
Here is a first pass at a teardrop sized trailer that is basically a Bowlus turned end-for-end and with the gores of flat material turned 90°:
And here is a shot of the rear fender of the Bowlus Papoose:
