In https://musicbrainz.org/doc/Style/Release#Language_and_script it says «If several languages are used in the titles, choose the most common language. For releases where there's an equal mix of two or more languages and hence no obvious answer, 'Multiple Languages' may be the best choice.» and «If several scripts are used in the titles, choose the most common script. For releases where there's an equal mix of two or more scripts and hence no obvious answer, 'Multiple Scripts' may be the best choice.»

I would like to make it so that even one instance of a differing script or language makes it a "Multiple scripts" or "Multiple languages" release, since that is entirely objectively how it is. If I have a release with 7 tracks written in Latin and 1 in Hangul, the script for the entirety of the Release isn't Latin. Same if I have a release with 8 tracks in English and 1 in Irish, then all the track names will not be written in English.

As it is written now it also conflicts with how it's done in practice. A release with 4 tracks in Swedish and 3 tracks in Finnish would use "Multiple languages" even if the strict reading of the guideline would suggest to use Swedish.

In relation to other tickets:
The change proposed here would also both be deprecated by and help with fixing up after tickets such as MBS-5452 and ... I'm sure there was one for Releases at one point, but I can't find it.
Also, I'm not sure how MBS-4501 affects/will affect this - whether that will cause language/script to be moved to be edited per tracklist (would make sense) and whether that would in turn make anything different for this proposal (I don't think so, but...).