It would be great if locked categories can be displayed in the categories list but have a lock or badge next to them and obviously not be accessible by users that don't have access.
I am looking to build an open community but have sections that only paying users of our site have access too and potentially have categories specific for higher plans. (e.g. top plans have a category on their own to chat with the dev team).
Seeing the locked areas might help pursuade users to upgrade their plan.