I still think that one Identity key and multiple device specific keys isn't that complicated. It's what we have now, except you validate in-event identity claims, and when you see a new revocation event prune the disavowed device events.

GitHub

NIP-102: Subkey Attestation by ynniv · Pull Request #1450 · nostr-protocol/nips

This NIP defines a way to separate identity from authentication using hierarchical deterministic (HD) keys. This allows people to use one key pair ...