We've taken a first step at identifying a growth-focused cause area that could be very cost effective, charter cities: https://www.chartercitiesinstitute.org/post/case-for-charter-cities-effective-altruism.
Planning to release an updated version of this soon that incorporates feedback received from the EA Forum and elsewhere.
To what extent do you think the benefits of trade liberalization are contingent on the economies of developing countries moving up the value chain into more complex products in terms of what they're exporting? Is there a non-trivial possibility that trade liberalization deepens existing resource curses (i.e., exporting but not processing raw materials) or is it far more likely that trade liberalization increases economic complexity?
And thank you for speaking to the DC EA group, I enjoyed your talk!
https://www.chartercitiesinstitute.org/post/case-for-charter-cities-effective-altruism
try this link, one above is 404ing for some reason