Love to hear about the different strategies. For the longest time, well after farm life became quite comfy coin wise around level 40 or so, I would not harvest animal products and instead, bought everything. Yes right, too lazy to keep up with the constant harvesting, feeding, producing feed etc.
Now that I actually want to master the feed mills as an achievement, I had to come up with a plan lol. Seriously, there is no plan though. Other than checking in every couple hrs. I sell most of the feed I'm making. I still prefer to buy milk, bacon etc. One feed mill is making goat feed constantly, the other one the other feeds in no specific order. More sheep feed when I know I'll be away for awhile, a mixture if I can check in every other hr or so.

