Primal DOES include dairy if your body can tolerate it. You're thinking of Paleo. Go for full fat. There are plenty of little articles Mark Sisson has written on the main page you can search for regarding dairy.... or buy the Primal Blueprint books?
I don't know anything about nutritional yeast so I'll let someone else handle that.
Apple cider vinegar is good for digestion or as a facial toner, I know a few people on the forum use it that way. You could use it in homemade salad dressings or dilute in water to drink, or find recipes that incorporate it.