I can’t think of any successful creator subscriptions/memberships, where the content is solely text.
There are two kinds of text focused that seem common - either early access/preview to a post for members, or pay to read below the fold. However, they largely depend on media too.
#[2]​ did you have ideas on restricting access to media (images/videos) in the same way, when they are referenced in those events? Would it likely mean additional N events are needed per file? And that’s likely still dependant on the file storage NIP.
I’m prototyping a CDN approach that’s more web/dns focused. If there’s a better approach, I’d likely change focus.