In digging around in the Google SketchUp 3D Warehouse, I found a model of a very interesting concept vehicle, called
Detaidon 3 wheel Car - Longrange Electric Drive Reverse Trike, 2F1R (click on link to download the model). Here's what it looks like:
Aerodynamically it is pretty good. And all 3 wheels are powered. My worry is the two flanks of (lead acid?) batteries -- they are low which is good, but they seem a little wide in the back.
I'll post more models as I find 'em. I hope that you can install the free version of SketchUp and try looking at these -- you can orbit around and look at them from all angles.