I can clarify the last point which is the most important one:
A reliable recommendation about a highest-leverage tactic would require a methodology that weighs different factors against each other taking into account that different factors have different spread and different weights, which is something a filtering check list is fundamentally unable to do.
Without the ability to quantify considerations, even if this means quantifying qualitative judgments, there is no way to make reliable recommendations because you try to integrate a disparate set of considerations which are—fundamentally—related to each other in a broadly multiplicative manner (see Effectiveness is a Conjunction of Multipliers for the clearest articulation of why that is).
A checklist approach destroys a lot of information and thereby misleads about relative importance, which is what you are trying to evaluate. Because some outcomes you are trying to alleviate are much worse than others, some are much more likely than others, some are much more tractable to attract than others, etc., a lot of this operates on variables that implicitly varying by orders of magnitudes across interventions and a checklist approach will massively under-represent the differences and is thus unlikely to point at the highest impact interventions.
This could be entirely explainable by what is most resonant with a broader public and the fact that many of the non-extinction risks have much higher societal buy-in / are much more legible to many more people.