It’s an interesting result, thank you for posting. I also did such tests back then and cows are intended to be the strongest livestock in max size pastures but I dont remember them to outperform so much. Reindeer was only added because people liked the “deer as livestock” option from other mods and it should be more a niche thing if not even moved to a special scenario but that’s another problem.
My first thought from your test is to increase required size, maybe from 30 to 36 for a cow and slightly reducing food output in addition. Or even more size but that will make it quite difficult to place pastures for at least 10 cows, which is the minimum to split a herd, if I remember right.
Cows should still be noticeably better on large areas than the others because it is more expensive or time consuming to establish such a big herd and also less fexible in terms of land use. Another small drawback of cows is that you actually need sheep to be self-sufficient on warm clothing.
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