How do you enrich your paid content to make it more engaging?

Hey everybody, I am interested in building products that works as a medium to present content for training professionals, content-creators, and story-tellers. Now I am searching for alternative ways to make paid-content engaging for the audience, especially for the subscription-based email deliveries. If you are offering your content through a monetization platform, like Substack, or getting paid through Patreon, Buy me a coffee, etc., how do you track your content's engagement performance and what do you to improve it to build stronger connection with your audience? Thanks for all great comments!