I don't see why you want to limit leveling speed. As I said, this, in addition to LP, is the source of your combat imba. People are already bathing in food. I accumulate cupboards of DDD's simply because I don't need that much damn AGI and Deer are so common for me. hell, CHA & Per is in such short supply, especially since the butter nerf, that I have never bothered to make a single BBB in the past few months. Boar meat is simply better spent on lamb sausages. Something I accumulated a cupboards worth in a few hours of hunting.
Food is only a problem for newbies who have to split their interest in balanced character development with limited production resources and settlement development. Either you start making food to feed yourself so you can have decent food while building defenses but risk having your development exposed or you survive off apples till you construct something moderately safe.
Personally I have not gone hungry in the past three months. I ate mulberries and apples twice. once when I neglectfully found myself at %4 and stuck light years from my village at a mining hearth with no alcohol. another time when I was moving resources out of Innsmouth and found myself trapped for a short time without food.
If you want gameplay balance, stop trying to create an arbitrary rate of character development. Just let it be purely about the acquisition, processing and consumption of resources. OF course, at the same time you'll need to add a double softcap to character development so that players cannot become stupidly powerful. Add 'toilets' or other method of reducing hunger that isn't, quite frankly, as ridiculous as what essentially amount to playing in the mud. Slow hunger to a reasonable rate OR alternatively, allow players to set their own metabolism based on a 'belief' slider.