If your consuming sub apps use roles and permission I suggest the sub apps deal with each user's role and permission on an app level.
Each sub app should consume the user as needed. Your o auth app doesn't need to know that info and it will get confusing.
For example you have a todo list app and a blog app. Your oauth doesn't need to deal with if a user in your todo app has a role to author articles. That aspect should be the responsibility of the blog app. Your blog app doesn't need to know if the user has a role to manage a teams todo list etc etc.
Now obviously banning a user (generally a Boolean on the user model anyways) the oauth server needs to know. But should the blog be able to ban a user, or the oauth app?
Yes, there will be overlap, but from my experience each app needs to handle it's self. The purpose of a single login is just that.
Now the oauth server though should have knowledge of applicable apps via the tokens, to control authentication of sub apps (cors headers etc). Probably a dashboard to handle users globally etc.