Overall, these are some great points and I agree! An interesting sidenote is that we are actually seeing an upswing in deficiency diseases in the West (hi scurvy and rickets). Also, modern food and drink has a lot of vitamins and minerals artificially added specifically to combat these diseases.
More on the point, have you and/or your company looking deeper into the cooking skill? So far it seems like recipes learned from that skill line restore multiple vitamins at once while having a longer decay timer. I wonder how having access to ingredients and a chef will impact this aspect of gameplay. I agree it depletes at a ridiculously quick pace, even after investing in the depletion reductions skills.