suggested language switcher

Hello, here I am making a suggestion for your extension, at the level of the language switcher, I noticed when a language was added, this is also added to the language switcher, the concern is that if a site is already well advanced and it takes time to translate, people see this language, so my suggestion is to be able to block the use of a language, i.e. have added a language to our site, but the language is only available with those who have the role (admin or those who do the translations for example) by default then when the staff and on that all the site and translated into the language, it activates the language for all the users.