I see trustworthiness as “this persons consistently behaves in a way that benefits our community”. Whilst high reading numbers shows the user has seen plenty of content, it doesn’t necessarily mean they behave in a way that benefits the community.
Perhaps instead of minimums values in the settings, we could have weighted inputs to result in an overall trust score? Something similar to the cheers score.
Perhaps things like staff/senior approval? A measurement for this might be number of likes from users in valuable groups(like staff). The more likes you have from staff the more points you get. Likes from TL4 score slightly less, and TL3 even less etc.
Perhaps things like contributions and involvement? E.g. Being accepted as a member of “Theme Creator” or “Theme Author” groups could add a distinct value to the trust score, rather than just setting a trust level explicitly?