I could be mistaken, but it looks like the only thing they are missing (and acknowledge - kudos) is the ability to create multiple sub-keys i.e. a "master" public and private key that only you know, with subsequent signing and certificate sub-keys that can be revoked that are used for actual use-cases. Considering this is the recommended arrangement of your personal keyring (per the Debian docs, anyway), this seems like a rather large oversight. Holding out hope it will be implemented in future releases, it'd be great to have another alternative to GnuPG. (And please, I get it - PGP needs replaced, it has flaws, blah blah blah. That's not what Sequoia is trying to do.)
Edit: I was wrong - if you read below, this is clarified.
Edit: I was wrong - if you read below, this is clarified.