Good article. It’s definitely tough to balance features vs. ease-of-use/clean design. I remember an early instance of this when Word for Mac (circa 1989, v.4) had a Full/Short Menus command that would either show or hide all the menu options.
To me, the logical solution (when practical) is to either allow the user to manually modify the displayed commands, a feature that I’m guessing few users actually go to the trouble to use. Or, better yet, have an option to adapt to the users way of working. So, if the program notices that the user has selected More > Mark as unread x times in a 24 hour period, then ask “Add this command to the tool bar? (Checkbox: Next time don’t ask)”.
Software should, more or less, be smart enough to adapt to the user instead of the other way around.