Cooking in 3 is never used except in rp. I think it should be a much bigger thing in 4. This could be achieved by making foods spawn less and making foraging and hunting more rewarding.
Cooking
In 3 you eat raw potatoes without blinking an eye. I think for 4 raw food should not only give you little nutritional value, but have a chance to make you feel sick.(screen wobbles a bit i guess and your character makes more noise or stumbles). So basic cooking should be a must, i made a post about advanced hunger earlier were i talked about how hunger should be split up into carbs, fats and proteins, but vitamins and mabye even Fiber should also be included.
Cooking should require some tools and preparation, but should be rewarding, rather than cold food. Opening canned food should take a can opener or a knife if desperate (but with a chance to cut yourself while fumbling with a can and blade). Cooked food should be a must for most meals, veg, meats and canned foods should give buffs if cooked well such as strength ect. Where as raw food can be eaten and even trained to digest well by a hardened surivivor but for new people who grew up on cooked food, it would make them uneasy, hard stomach could like a starting buff/trait that could let you eat raw veg for little punishment.
Food rotting
Basically food should go of without referigeration, meats quickly in particular, so salting and cooking/smoking will preserve you food.
Farming
Insteed of sacrificing half you crop to seeds like in 3, some veg like potatoes should be planted directly, others could have seeds taken from them before eating with a chance of failure, crops should be different sizes, like small potato, large potato, medium potato. And some will grow poor to eat depending on care. These duds would be the best choice to replant and save the best for eating, each plant should give more than just 2 with a good farmer, some plants sold grow first, then give of fruits without having to regrow compleatly.
Foraging and hunting
Better hunting has been promised, like skinning animals. You should always get meat from animals unless you shred there body. Small animals like rabbits and squirrels should be common, and larger animals trackable, giving plenty of meat. Berries and wild vegetables should spawn, but only good foresters should be able to identify what is dangerous and what is edible. Some berries will look the same and only skilled people will get names when hovering over it in the inventory. With a hardened stomach some roots could become a menu option. Also sticks and logs and stones can be found laying around, so you don’t have to chop or mine to get some resourses.
This would greatly impact surivival gameplay, i think with things like foraging for food and supplies would really give unturned that great survival touch, i think that one day we can have pure wilderness surivival servers, that would be cool as very thing would need crafting. But anyway that’s just my opinion.