> list [...] sounds like it would be very useful...
I think it's more dynamic and adaptive than that. That two people, at some specific time, seemed to have a pattern of causes of (un)happiness, would likely be of only limited use elsewhere.
Googling turns up innumerable recommended/avoid food lists... with some overlap. :)
But the main lesson I drew, was the applicability of wisdom from ops, experimentation, system design, debugging, and so on.
Patterns exist which are usefully noticed. Even though many are short-lived, and are mixed with noise. Expect them to change.
Keep logs/notes. Including about yourself. Because it's hard to keep track of things, let alone see patterns, and notice them changing, when you're distracted and exhausted.
Witness a "you know, it seems like maybe, the team might be tired and unproductive on the day after we go drinking all evening?" :)
It helps if you can find "a place to stand", something that works, at least for now, that you can build out from, while keeping things working, and backing off when things stop working. One new food at a time.
When things are broken, it's nice to have some simpler setup(s) you can fall back to. Small easy simple minimalist. Someplace familiar to stand and debug from. A set of "these are easy and have never seemed a problem" foods.
A-B testing; falling back to "more likely to be good" state; divide and conquer search; the idea that you gradually introduce changes and see how they go; ... all are useful.
KISS.
No doubt a lot of professions feel their training was great preparation for supporting a child. It sure seems that way for engineering. (There is a book series to write, if it doesn't already exist... "The <profession> guide to <age> children".)
Good luck. I saw a story once, about a mom who captured a picture of their child every day before he left for school, because she was convinced she would never see him again... the person who came back later, was always someone a bit different - familiar, but not someone she'd met yet. So a random silly bit of old-guy advice: savor the dance, for it can't be captured, is a sacrilege to retard, and escapes irretrievably beyond reach every day.