A system where I can mark other people as trusted and see who they trust, so when I navigate to a web page or in this case, a Github pull request, my WoT would tell me if this is a trusted person according to my network.
If someone showed up on at-proto powered book review site like https://bookhive.buzz and started trying to post nonsense reviews, or started running bots, it would be much more transparent what was afoot.
More explicit trust signalling would be very fun to add.