Public read relay, but only members can write to it.

Publish all news articles and events as long-form text, and nip-52 calendar events, respectively.

DMs for private comms between org staff and members.

Biggest problem: org-owned accounts and integrating into existing identity system. As much as we like to say that Nostr is the internet-native identity system, in order for existing large orgs to adopt, there HAS to be a way to log in with trad OAuth or ADFS or something and have it as Nostr Connect signing device.