About the change for food: that's attempt to turn food in nothing more than a weak option for dealing with only very small hp-loss. So it'll still help a bit, but no one would ever think about healing up from 5/50hp to full 50hp with food.
I can see how some kind of food could heal exactly 1 HP just like magical Goodberries.
I can also see how some food would make you lose HP. Raw potato and 1kg of cheese can't make you feel any better or regain your stamina.
I very much like many of your ideas. They are likely outside of Larian's plans, but for a video game: Larian's homebrew < D&D RAW < your propositions.
