In my case I want to enable all users, current and new users to be use the magic login facility no matter what user group they are within.
Some form of checkboxes within the CP or array within the config file would handy.
My use case is, when a user is created they are auto assigned to a user group called member, it would be good for these users to automatically be able to use Magic login, as well as users I then assign to Admin or other user groups that are then allowed via the plugin settings/config.