Hi! Good to know that OpenPhil has done a grant on societal collapse!
I'm sharing here the post I made about energy depletion as a major risk: https://forum.effectivealtruism.org/posts/wXzc75txE5hbHqYug/the-great-energy-descent-short-version-an-important-thing-ea
I provides a lot of data about the link between energy and growth, how the financial system could crash down in case of a too important recession. I think you can find a lot of valuable information there, I spent quite some time reading on collapse and aggregated some resources there.
(We met in Berlin, but I don't relember if I had shared it, I was supposed to do a project on collapsology at ALLFED)
Nate Hagens is also a very valuable source of info. This 30 minute video provides a lot of inshight on the coming challenges: https://www.thegreatsimplification.com/animations
Sounds cool, looking forward to read that! Probably you're already familiar: Gwern might be a good inspiration and as I understand he publishes his living lit reviews and then published updates to them as part of a newsletter like so: https://gwern.substack.com/p/april-2021-newsletter