After enabling, loging in once and disabling the default Administrator account, I can see the user folder named 'Administrators' inside my Users folder. How can I hide the folder like it was hidden before?
As commented by user @Darius, I successfully disabled the Administrator account via command prompt and then used delprof to delete the remaining folder inside the Users directory.
Note that deleting this folder means that the Administrator account will run the entire set up process every time. To avoid this, I've added a password to the Administrator account, disabled it, but left the user folder in place. Whenever I enable it and log back in, all my previous settings are restored.