Here are a couple more ideas:

1. Schedule your pieces to be published a day after you finish them and allow your patrons to access them first, before anyone else, and share private notes (In Draft mode, it will feel exclusive).
2. Start a Discord channel. They have a cool integration with Patreon and can open up more tiers for you. What should you write there? Well, most people don’t know about writing but maybe you can run a poll to have them select piece options that you will write about. Or what you will write first. Have an exclusive Q&A with them. The options are truly limitless :)