I would really prefer a cow for the cream (butter) and the cheese (cheddar, etc.) But the start-up expense of a cow is much bigger, the hay needs, etc. I can stagger breedings of my goats and not have a dry period (in theory....buck escape means I had to dry off the gal that was to milk through this spring) but to have two cows and feed a non-producing one for a big chunk of a season.....no way!
Also, if a cow needs the vet, you get them here in a hurry and pay hundreds and hundreds and still may lose her in this area. Goats....sadly.....are more expendable. There are always doelings coming along to replace them.
Breeding is a simple thing, too. Cheap if you can own a buck, or buy a buckling in the spring, breed him to the does in the fall, and sell him or send him off to freezer camp. Or keep him for next season but not for his daughters....goats are fairly inexpensive to feed, especially if not on grain. Although they generally don't need much grain. Better yet, bring your gals to visit a neighbor's buck.
It was a drought summer and it cost me an extra $250 or so in hay to get 7 goats through the summer, normally I use almost no hay. If I had even one cow......yikes. Would've cost me a small fortune.
But I would love a little Jersey cow. I would only get one if I had too much pasture, enough to get me through a drought summer and enough to have fall pastures to rotate her into through the winter if the snow isn't too deep.