I have a vague thought that as you meet ppl IRL, you can validate each other's public key (if you choose to). When you see someone with a heavily validated key (or validated by someone you trust), that would act as high trust. Theoretically with this model, you could have multiple public keys; but each would have to be validated separately. (You could validate differently: a personal key, a biz key, an agorist key, etc).
On the flip side, if your key is validated by someone considered untrustworthy, you'd lose a lot of that trust. But you could generate a new public key, and begin to work the room again. (so you're never completely out, just need to rebuild trust.)