I guess I make my gravy differently than most folks.
We usually use a whole pound of sausage in our gravy, then fry another pound up into patties to go with. But there isn't that much fat in good sausage, so I usually add a couple of tablespoons of bacon grease. I think that helps the flavor, too.
The trick to not having greasy gravy is to add enough flour to soak up all the grease. The roux should look dry. Once you get the flour stirred in, take the pan off the heat to add the liquid. Add the milk a little at a time, about 1 cup to each tablespoon of flour, stirring it to get out any lumps. The mixture will look thin, but will thicken up as you cook it, like a white sauce.
In the past, I made a lot of "cream gravy" with plain old bacon grease. For that, you need a lot more seasoning, as bacon doesn't have all the spices that sausage has. I always found that about 1/2 tsp sugar made it taste a lot better. At the end of the month, when the cupboard was bare, a person could get filled up real good on cream gravy and bread.
We get by with a little help from our friends