One area that has often been discussed as an EA or meta-EA cause area is rationality development, whether that be in the form of "raising the sanity waterline", providing relevant training to certain key people in order to empower them, or something else entirely.
What aspect of this strikes you as most interesting or relevant? What would you be most excited about seeing out of a new group or project in this area?
I've become pretty pessimistic about rationality-improvement as an intervention, especially to the extent that it involves techniques that are domain-general, with a large subjective element and placebo effect/participant cost. Basically most interventions of this sort haven't worked, though they induce tonnes of biases that allow them to display positive testimonials: placebo effects, liking instructors, having a break from work, getting to think about interesting stuff, branding of techniques, choice-supportive bias, biased sampling of testimonials, etc etc etc.
The nearest things that I'd be interest in would be: 1) domain-specific training that delivers skills and information from trained experts in a particular area, such as research, 2) freely available online reviews of literature on rationality interventions, similar to what gwern does for nootropics, 3) new controlled experiments on existing rationality programs such as Leverage and CFAR 4) training in risk assessment for high-risk groups like policymakers.