I need a license plate frame like I need tap-dance lessons. Do you know which type of frame looks best?
None. Know why? Frames are stupid.
Whenever I get a new(er) car I always go directly to the stainless steel fastener section of a hardware store and but S.S screws for the license plate. I put the plate on and Voila!
But, f you want to sell license plate frames, or anything, make it “green” or “healthy” (I hate that improper use of the word. It should be “healthful.”)
Make the frame out of anything recycled, neck-ties, Girl Scout Cookies boxes, beer cans, old tires, etcetera…
Or… make them gluten-free and low in calories and trans fat, and put in a little salmon and kale.
You could also resort to that “shaming” thing. Just have some of the purchase price go to save some kind of endangered animals or starving people or out of work celebrities.
Voila! You’ve got yourself a winner! 
CSA