Really excellent writeup. I think many people are squeamish with the idea of "personal opportunity cost" also because in their experience "personal numeric value"==easy unhealthy way to measure (seemingly) one's worth and to compare two individuals value ("I earn $10/H more so I'm better than him/He earns more so he's better than me"), which can be unhealthy. But it should be approached with as little ego (in the self-worth sense) as possible and as a tool you can use to better self-reflect on your life and your decisions.