I think that approach is valid, but I don't know if it's worth trying to arrive at the "best" judgement of whether someone should be banned or not. It's better to foster an ecosystem in which relays can ban freely according to whatever absurd criteria they decide and users and clients can pick relays wisely according to their preferences (most clients are not ready for this as far as I know, but it wouldn't take much).

On https://pyramid.fiatjaf.com/ my plan was to somehow let hierarchy of the relay somehow police itself. If people higher in the tree don't like someone down they can just ban that person -- and if they are not in the same subtree their vote still counts more than someone that is lower. Or something like that.

Of course I didn't implement any of that yet, I was even blocking kind 1984 by mistake until a minute ago.