Then if you need those features on a regular basis, you have to make a lot more clicks to access that hidden menu. I personally really like the Microsoft menu paradigm where I can either click on the File, Edit, ... menus or press Alt and then a memorized sequence of characters. It allows for discoverability as well as efficiency.
The Emacs equivalent also works nice: press a memorized key binding for something that you do frequently, or press M-x to type into an autocompleted (and fuzzy searched, with the right packages) list of commands for some particular functionality.
Or, in case of Emacs: just bind the M-x feature you're using to a key.
The overall principle is sound, IMO: present the "simpler" UI up-front to not overwhelm newcomers, but have advanced features available and a means to bring them up to front of the UI, for repeat users.
The Emacs equivalent also works nice: press a memorized key binding for something that you do frequently, or press M-x to type into an autocompleted (and fuzzy searched, with the right packages) list of commands for some particular functionality.