In v3.21 support was added for redoing the last undone action and repeating the last run action or action group. This was a very useful addition.
My suggestion is to additionally replace the Edit > Undo/Repeat single entries with cascaded lists of recent actions(or action groups), with the number of files affected next to each entry. I have found this feature in MusicBee and I find it very useful.
Musicbee screenshot:

Mp3tag screenshot example:

Thank you
PS. Using latest Mp3Tag 3.24b x64 on win11.