I've been smoothing the bottom and after gluing in some small patches, the diffuser fins are much more even and straight:
(click on thumbnail for larger versions!)
I need to work on the right side and then I will glue up the wheel skirts, and then start fiberglassing the bottom. A windshield (from a Smart ForTwo) will be needed fairly soon as well.
Yes, I think some of the ways I am building CarBEN EV5 are usable for other projects. I am following some of the stuff I have seen others use here on EM.