Ability to change the size of normal notes
Currently, in Style -> General -> Sizes, you can adjust the size of small notes (and small staff / Grace notes / small clefs)
But nothing about the size of the "normal" notes.
Apparently, this feature is missing (see - in French forum : https://musescore.org/fr/node/187611, and https://musescore.org/fr/node/188016#comment-701011) for people who would have some vision concerns, and/or for educational purposes (for kids audience I guess).
And of course, the ability to change the scale (in Layout, or Staff Properties) does not suit them, since it increases or reduces the entire visual of the score.
There is a possible workaround (shown here : https://musescore.org/fr/node/187611#comment-696876, with test files: petites notes 1.mscz and petites notes 1_0.mscz ), but it's a bit twisted, I agree.