Interesting thought. Especially about the potential of integration of Nostr into other every day apps.

To think out loud, about what I would want, would be a main set of keys; verified via NIP-05 or a better protocol back up on a hardware wallet and/or Yubikey; and from that set of keys the ability to generate a new npub & nsec that I could use on any other platform for any other reason.

That would essentially allow me to have multiple sets of keys all managed (and potentially verified) from the main npub and nsec.

Or maybe I've spent too much time here and my brain is turning into that of an Ostrich.