It would be nice and useful to have the possibility to save extra public thumbnails for private videos somehow and use them later to present those private videos to users without actual valid URLs for private ones.
This feature would allow keeping all relevant data together in the same place (together with the videos) and not saving them somewhere else, which should lead to a simpler application environment.
The solution, how to relate the identification between private videos and their public thumbnails, can be realized differently. Still, the simplest one would be probably using “videoId” again, now with a new parameter syntax. This new feature shouldn’t compromise the security of such private videos in any way.
Thanks for your opinions.