It is my first post and I looked around whether similar proposals are around already but I couldn't find any.
When playing with livestock I always found the system is biased against grazers because non-grazers don't need input at all.
Proposal 1) Change livestock so it needs regular food intake over its whole life. This should be balanced so that the food necessary to grow up is at least as large (better double the amount) as what slaughtering the adult animal yields. Food can be vegetation for grazers, meat and fish for carnivores (either portioned or to feed very large beasts whole animals), eatable plants & plant seeds for herbivores. (This would make sustaining large, fast growing carnivores far more challenging, while giving you a chance to keep larger grazer-herbivores alive by adding some cave wheat to their grass intake.)
Starving should have the danger of even domestic animals reverting to (temporary?) wildness. Pets should be fed by their owners, all others by animal caretakers.
Proposal 2) Make leather yield dependent on size (sth. like bones/5 ?) with a healthy minimum requirement of size 20000 or so. This would give an incentive to bother with larger animals that would be harder to sustain with proposal 1 in place and would avoid exploits like unlimited free chicken leather. With the higher leather yield for larger animals some large leather products (leather armor, robe ...) might as well require more than 1 leather to produce.
Proposal 3) Give an option to castrate male animals (with an associated risk of death). Optionally there can even be a veterinarian skill, which would handle this and which would take care of animal injuries that you toggle you want to care about. (With carnivores harder to raise acc. proposal 1 you might want to heal your precious war lion instead of just waiting for the next generation that comes for free.) Maybe the veterinarian skill can modestly cross train other medical profession giving an option to train your doctors a bit w/o ruthless designs like falling experiments.
Proposal 4) Give an in-game option to wipe out all domestic animals from the death list.
Proposal 5) Make fat / tallow sortable without going through each kind of fat / tallow (including ten dozen forgotten beast fats/tallows) individually.
Effect: Livestock would turn to a means of converting grass / plants to meat (+bones, leather, fat) and would require directly or indirectly either pastures or plant input to work (as in real life). Cheap exploits like surviving solely on input free dog meat or breeding dragons for your daily dragon egg would end, the carnivores would be much more precious than before, grazing (therefore controlling large enough pastures) would be more important and there would be an incentive to build well designed stables (with the food supply close to the chained animals)