How to completely "reset" an Oracle instance? I'd like to drop all entities from an Oracle instance. I want to delete all tables, users, indices and so on, just like as if it would be a freshly created instance. The result should look, or at least closely approximate from the viewpoint of the clients, as if I had completely deleted and then reinstalled the instance with the same settings.

Doing this with a complete wipe/reinstall is slow, and it is not easily automatizable. I am looking for better options, but it is a possible solution, if there isn't.

Dropping the schemas is not enough, because some entities still remain in place (for example, users).

Is there an easy way to drop everything, to reach the initial clean and empty state, but more quickly?
There are just so many things in the database in addition to user data that checking all of them would take a considerable amount of time. Also there are some parts that were not meant to be removed at all, for example the history of used features (for license audit).

Sure, you could try to check all non-default configuration or rerun catalog scripts (but whats the point of that? creating a new database does exactly that). Its easier to just drop and recreate in 15-30 minutes depending on your selected components.

PS: there is no reinstall involved in dropping and recreating a database.