[blipvert]

Well, yes, pick your poison.

But for just getting access to role accounts then I find it a lot nicer than distributing public keys around.

And for everything else, a periodic Ansible :-)

[gnufx]

Public keys (for OpenSSH) can be in DNS (VerifyHostKeyDNS) or in, say, LDAP via KnownHostsCommand and AuthorizedKeysCommand.