Ok, I've thought about the cow game, and I think that it would be better gameplaywise (not necessarily meat eating propoganda wise) if you play someone raising a cow that wants to be eaten. Your goal is to keep the cow fat, happy and uneaten. So the cow will be in a pasture grazing contentedly. And occassionally you'll need to herd the cow so that it doesn't overgraze one spot. Every now and then a random event will occur, like the cow wants to take a bath. So a tub will magically fall from the sky and the cow will get in. Sometimes the cow will just take a bath. Sometimes the cow will chop up some carrots and onions and build a fire underneath the tub. So your avatar will need to stop the cow before she actually manages to cook herself. But the longer you wait to stop her the more happiness points she'll accumulate.
I think your avatar should have a stamina bar, and doing things liker herding the cow would use up stamina points. You can let your avatar sleep to regain stamina, but then he'll be slower to react if the cow is overgrazing or cooking herself.