It'd be great to have a long tap actions for icons/buttons on a touch bar. E.g. long tap on a "volume down" button of a volume widget might turn volume off immediately, and long tap on "volume up" might unmute the volume back to the previous value.
There may be some specific scenarios for different buttons and widgets. I may write them down if there's a chance to have this feature in next releases.
Best,
S.M.