Well here's one, I got a ticket for no backup lights on a rental Altima in SF.
I mailed the ticket to the court with a letter and copy of the rental receipt and told them to bill Hertz.. Never heard back..

Backup lights are to tell others your backing up,,, not to help you see, that's a side benefit.

 

If we are talking lenses, I typically enjoy seeing ambers up front, but I utterly despise the look of amber and red lenses clashing in the rear.

Bulbs however, I always like amber front & back for lane change indicators.

It's entirely too much of a personal subject though, everyone is bound to disagree.