My solution was to self-host PowerDNS and then sign up for the free DNS mirroring from hurricane electric. That way, I can administer my DNS records any way I want (these days I usually just manually edit PowerDNS's sqlite database) and if/when my PowerDNS server goes down, hurricane electric is still serving my records so the domain keeps resolving fine.
Unbound is caching, not authoritative. Zones with dns records are served from authoritative DNS servers such as bind. Unbound asks authoritative servers for records and caches them locally, giving faster response and reducing load on authoritative servers.
