The 'CSS class for video' and 'CSS class for audio' settings are low value and could cause issues.
Today I came a cross a site where for whatever reason these two settings were empty.
The result was a totally borked video JS player - most of the video area is overflow scroll bars and only a small percentage of the video shows.
See the attached screenshot - no-video-js-class-breaks-video-js-in-boost.png
The value of being able to change the CSS class for video js players to something else seems pretty low to me. If you needed to change the visual appeal of the video js player it would be easier to just override the CSS class styling. As it stands now, for theme developers, it also means that there is no dependable CSS class that you can target for making minor adjustments to the way the video JS player is rendered.
Many administrators aren't developers or CSS gurus- giving them settings like this is just asking for trouble.
Also note that the settings are not advanced settings.
Personally I'd be tempted to remove these settings completely and keep video-js as a hard coded class. However, if there is actually a use case for an extra class, it should add to, not replace the existing video-js class.