For a simple shape, I like the idea of a split down the center ice cream cone from the low beltline up and then vertical slabbed below that with 3 wheels - tadpole styled. Rear direct drive at speed on the highway, hub motors up front that have no drag at speed for accel/decel.
I just don't know how aero the shape would be. The ice cream cone itself is extremely aero so whatever affect the vertical sides would have is the big question but it would keep it simple to fabricate.
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