Nostr NIPs seem to lack an OpenPGP-style web of trust. Signing your Nostr public key with your OpenPGP secret key might be helpful. OpenPGP has cool features such as non-repudiation and key revocation, etc. Personally, I like "Trust On First Use" (TOFU) approach. For instance, I might partially trust a "Satoshi" PGP Public key I saw back in 2008.. just like through TOFU idea. If I am not mistaken the TOFU idea was implemented on GNUpg in 2015.. here is the Original Paper https://www.gnupg.org/ftp/people/neal/tofu.pdf