This is a great post, and giving how detailed it is, I wanted to include something I wrote relating to the problem with how food currently works in BG3.
I think food is too powerful as it stands, even if it couldn't be consumed during combat. Currently, it already invalidates numerous class spells and abilities, such as "prayer of healing" for example, which heal players when out of combat. Why would a cleric waste a spell slot to heal their party members out of combat, when the party could just eat the overly abundant food offerings to heal to full every time.
If food is to be included, I think players should only be allowed to benefit from a certain number of food items per day, and only while outside of combat. As players level, they will prioritize keeping higher quality food with them to make each use count. This also creates more player choice and strategy, to decide when it is worth it to restore health out of combat, rather than mindlessly auto healing to full after any damage is taken. Higher quality food should be rarer, so that the common items like apples would still be used at times when the player doesn't suspect as much need for healing before the end of the day, since they want to preserve the good stuff for more important moments.
