[dangles red meat]
Heh. Welcome. (I'm a little curious how you could post a picture at Permalink #4, and not be up to 5 posts currently)
My own obsession is the VW Beetle, and my reckoning is half from aero and half from drivetrain. Here is the drivetrain cRiPpLe_rOoStEr mentioned:
It wants 400volts, but for 50 mile range you could use lead acid batteries and a buck/boost inverter.
What I'm curious about is the use case. Our member slowmover is good on that (driver input costs gas!). One of the biggest changes you could make is wheels and tires. You might be able to swap out two sets for different scenarios.
Edit: I went back and read some more. The nuclear power and vortex generators can go into the Unicorn Corral. You can induce turbulence with sandpaper. The human-power racers have something I think they call zip-tape[?]
I fully support the aerocap that extends over the cab. I'd include a visor that extends over the top 1/4th of the windshield, big-rig style. You could integrate the tailgate from a Dodge Magnum. It's whole roofline is optimal, just graft the whole thing onto hinges.
Else, consider a material like Polymetal:
PREFINISHED! And it can be rolled, sheared and braked by hand, as these samples were. Stiff as 5/8" plywood at 1/10th the weight.