Yes, it might seem counterproductive, but a lot of people who are new or still hesitant about raw milk would heat it to at least sterilize it. But 180 degrees is too high for raw milk.
I also depends on whether you want raw yogurt or yogurt made from raw milk.
Also depends on preference, if you want runnier/thinner (less heat). If you want it thicker (more heat).
For thermophilic cultures, at least the ones that I use, you still have to heat the raw milk to 160 to activate the mother culture, then you just incubate it at 110. Even when I heat the raw milk to 160, the yogurt still tastes better to me than yogurt made from pasteurized milk.
It seems you are using a mesophilic culture since you let it set for 24 hours. If I let thermophilic cultures set for longer than 12 hours, it separates beyond repair and the bacteria begins to die. For mesophilic, I do not even heat the yogurt at all, not even to 110, but just inoculate it at room temperature and let it be for 24 hours or even more. Those are most of the Northern European or scandinavian type yogurts.
One way or the other, I love homemade yogurts...