I love the programmatic payments. what's the key rollover story? social key recovery? IMO these are table stakes for PKI to reach the general public. There's a technology called KERI (key event receipt infrastructure) that I'm bullish on, has to do with signing new keys with the old, with witnesses, with configurable threshold cryptography (m-of-n key reconstruction)

my favorite part about that last one is the possibility of social key revocation - if you're in a community misbehaving, the same people you trust to save key fragments in case you lose your private key can conspire against you to lock you out of your account, a kind of cryptographic ban hammer.