[namank]

Sounds like you don't have enough data - go spend a year on energy, then in AI, then in healthcare to learn about them. Then you'll have the data to make a decision that you can probably be happy with.

Also note that this decision paralysis has already led you to one regret: not getting anything done. If you still believe you should pursue regret-minimization, then I suggest start doing something (anything, really) right away.

And I would be careful about the "should" vs. "want". Thinking about it that way will just never make you happy because you'll be always wondering about the path you didn't take. I don't know what the answer is but it's just something to be aware of.

Personally, I think about "should"s. Only after that do I think about "wants". Then I start by doing the wants and try to see how it would merge with a should. Because someone once said, "Start by doing what's necessary; then do what's possible; and suddenly you are doing the impossible."