I don't see what I thought were the obvious answers, so here they are. The foundations are elsewhere on the site, but they seemed missing from this list.
Reputational: Expect Bayesian masters to participate in other scientific fields. People who make more discoveries in other fields get more street cred among rationalists, especially when they can explain how rationalism helped them make the discoveries. Obviously, this is a long-term process that doesn't lend itself to improving the art quickly.
Experimental: This one's a two-step process. First, ask a larg...
Within-group differences are larger than between-group differences in most of these domains, so I'd rather make it easier for both groups to deviate from their group tendencies than to try to identify more group tendencies that it will be hard to deviate from.