I've noticed that a lot of beginner editors seem to be unaware of the style guidelines (which is understandable, since there are a lot of them!). I think it might cut down on the need for a lot of edit comments and cleanup if the release editor UI guided users toward relevant guidelines when it looks like they may be making mistakes.

MBS-10858 already tracks warning users when " feat. " appears in a track title (likely because Style/Artist_Credits isn't being followed).

Capitalized words like "The", "In", or "Of" in the middle of a title usually mean that Style/Language/English isn't being followed, although there are enough exceptions (e.g. Style/Language/Japanese) that I'd be reluctant to nag non-beginner users about this.

Capitalized ETI like "(Instrumental)", "(... Mix)", or "(... Remix)" at the end of a release or track title usually means that https://musicbrainz.org/doc/Style/Titles#Extra_title_information isn't being followed. Warning about that seems low-risk to me.

One tricky part is that I'm not sure when or how it would be best to prompt the user. I don't think that any of these things should be blocking errors like 'A format is required. If you don’t know it, tick the “I don’t know” checkbox next to the format dropdown.' on the tracklist page when a medium format isn't selected.

If these are non-blocking, it's not obvious to me when the user should be prompted – displaying a bubble in the tracklist editor right after the user enters an improper title could be annoying, since they might've been about to click "Guess case". Maybe that's less of a problem if this is only shown for beginner editors, though?

Anyway, I'm curious about whether other people think this makes sense and if so, how it could work.