Haha loving the little pun. The screenshot looks great!
You’re entirely correct in your thinking. Sharing publicly is rather complex (from both a security, privacy and performant perspective), so at the moment you can only share one card at a time. However, in Supernotes 3.1 we will be releasing Custom Collections allowing you to save a set of filters permanently as a Collection. This paves the way for making public groups of cards. There is no ETA on public collections yet, but it’s something we definitely would like support.