Dairy substitutes for various purposes I've been considering trying to reduce my dairy consumption for environmental reasons (I've long since reduced my meat consumption), but I'm not sure what to use for various substitutions.

I generally go through one to four gallons of whole milk per two weeks. Uses include:


A little bit in scrambled eggs
Pancakes, muffins, popovers, and the occasional custard or quiche
Yogurt (easier than buying separately, probably cheaper, and I strain it to be much thicker than anything I can find in bulk in stores)
Oatmeal, both cooked with milk and then supplemented with yogurt
Soda-bread, made with yogurt rather than buttermilk
Hot cocoa
Mac-and-cheese (not box mix, so milk and cheese and butter are all involved)
Milk-enriched yeast bread


And then there's butter and cheese for various things, but I buy those separately rather than making them from milk, so replacing dairy milk wouldn't affect that.

I would expect that the hot cocoa, the yeast bread and quickbreads, the scrambled eggs, and the oatmeal, could work simply replacing the dairy milk with almond or oat or soy milk, because all of those would work with water or with no liquid at all (just less tasty/nutritious). I am less confident that that would work for making custard, quiche, or a properly thick sauce for mac-and-cheese (even allowing dairy cheese), since I'm pretty sure the milk is relevant there chemically/structurally, but I'm not sure. I have a bad feeling that I could not make an acceptable yogurt (both for flavor and for adding sufficient acid to soda-bread) from nondairy milk, or at least not without significantly more effort than the fairly trivial process of making yogurt overnight in a slow cooker.

Is there a single replacement I could buy for dairy milk for all of these products? Lacking that, what replacements should I use for any given portion?
I’m a huge dairy lover but I recently found out a couple years ago that I am lactose intolerant and had to make the switch over to non-dairy almost everything. 


If continuing to use butter isn’t a problem for you, keep that one. I bake a ton and butter is still the best option for popovers (my grandma was British, I make them every Christmas) and any sorts of breads. If not, subbing in margarine or a vegan butter (basically margarine) works well too.
For 90% of what’s on your list, unsweetened original flavor almond-milk is my go-to, oat milk would work well too. Both of those have the mildest flavor and bake well too. Any sauce that needs to be thicker or richer, sub out soy milk instead for chowders or say a bechamel sauce, which could work with almond-milk as well if you just added a little cornstarch and non-dairy or goat cheese, thickens it like a charm!
-Non-dairy yogurts and cheeses have come leaps and bounds in the last 10 years! For cooking I’d recommend using either goat-milk yogurt for the tangy-ness or a Kite hill, Silk, or Lavva (which has a really tangy unsweetened one I just used to make a tzatziki sauce the other day, came out great!). For non-dairy cheeses, the best are from Lisanatti Foods (almond-milk mozzarella block), VioLife (their cheddar slices and Parm block are great), or Chao (great slices of cheese for sandwiches).