Clarify what you're measuring
It seems like "cost vs. impact" is the main measurement for the effectiveness of a cause, but how are you prioritizing "impact"? (ie: reduced deaths, economic growth, environmental healing).
Specifically, more research has been done on the economics of happiness, and have you been successful in quantifying the impact certain causes have on happiness? Many "first-world" causes (ie: Big Brothers/Big Sisters, foster care, etc.) have more to do with increasing a person's self-worth than health or economic concerns. While these don't rank high in your models (presumably because of the cost of these programs with lower quantifiable results), the personal connection is often more beneficial to the giver/volunteer than sending money to a faceless organization.
This topic is discussed here: https://80000hours.org/articles/the-meaning-of-making-a-difference/
"the personal connection is often more beneficial to the giver/volunteer than sending money to a faceless organization"
We mostly focus on benefit to recipients.