[Otto]

I said an elliptical or circular planform bandana, hinged or pivoted at the back corners.

Perhaps a better analogue would be the hinged/pivoted visor on a motorcycle helmet. In this case, maybe 4-6" high, so that it could easily be raised and locked in up position just aft of the front bumper. This for around town driving, where those pesky parking lot railroad ties and curbs eat low hanging fruit.

As for nose shapes, few advanced cars now have anything but a circular or elliptical planform, i.e, as seen from above. Google images of Porsche, Ferrari, etc. In profile, these typically have gently radiused leading edges, often with ~3-6" radius. Lower lip (ie.e, splitter) is often smaller radius, though, maybe ~1/2 the upper.

BTW, thanks for the pics, esp. Ford Probe IV. My plan for headlight covers and front wheel fairings for my Porsche 944 Turbo bears some resemblance.