NIP05 is kind of a self certification of pubkey tied to traditional DNS.

So something better may be a form of peer attestation of your pubkey.

1. Using strictly NIP05 semantics, this could be a change to the NIP (or really another NIP) that allows specifying multiple NIP05s for one pubkey. This can of course be gamed by a single entity representing as multiple domains for that pubkey.

2. Another possibility is local labeling of accounts backed by in person verification. Kind of like trust levels for pgp.

3. Or perhaps a web of trust scoring algorithm from your account perspective to others based on how many people you follow also follow an account, activity levels etc.

Every type has pros/cons