I think most people answered your question without reading it. They must be mind-readers.<p>In my opinion there&#x27;s only one way to do this. Admins who are all powerful, and non-admins. None of this complexity of super-admins, etc.<p>Admins have access to everything.
Groups have access to things given to them. Users in more than one group have access to the set of all things their groups have access to.
Users without a group are really just users in a group of 1. They have access to things given to them.<p>People who ask for more complicated permissions than this are asking for foot shooting abilities, where people have access to things they don&#x27;t mean to.<p>The rest is up to UX. Notify other admins when one behaves badly. Confirm admins really did mean to remove themselves from the admin group.