I feel it would be helpful if the Command Editor that shows when defining a new button could include an optional "Input:" field that supports a regex validation string.
When populated, the input field would show with the button label text inside an input box. The command / script would then be able to include the user entered data and be called in the normal way.
My thinking is the regex would be used as a mask so only valid text (or numbers) are entered by the user.
When on a toolbar the button would actually show as a text input box. Text entered by the user would be validated by the regex string defined in the command editor.
Entered where? Buttons don’t take input, except via the various codes to show a dialog and insert a result (where a single regex wouldn’t make sense as each dialog may need a different one).
I think that is the real feature request here, then.