I always cook up the neck, giblets, heart and liver with onions celery and carrots. I only strain off the broth, I have never added the chopped up meat to the gravy.
I have a funny story about making gravy, at the inlaws. My mil had bought 6 packets of turkey gravy mix and 6 boxes of stove top stuffing. I went shopping and bought fresh stuffing ingredients including pork sausage meat and fresh herbs. I also put the neck etc in a pot with onion, carrot and celery to make a broth for the gravy.
I got the stuffing made and the bird in the oven. The broth was simmering nicely and I went for a walk. Came back and my fil decided to help and poured the broth down the drain and left the well cooked neck, vegies etc sitting on a plate. I could not believe it.
I like to switch up the dressing ingredients, but my family likes the same old meal. I often will cook a turkey in February and make interesting dressing to please me.