I have the giblets and neck in the roaster pan i have under the bird in the smoker to catch the drippings. Also have some mirou pioux in the pan as well. I will pulling out thye veggies and giblets (dog food), and make my roux with the drippings. I add a little salt and pepper and chicken broth..that's it. I usually will make the mirou pioux and saute the giblets and neck in a pan the night before and make a turkey stock from scratch for the gravy...a little lazy this year.
If ya want, you could add some fresh chopped sage or even dried and maybe a little cayenne if you like. If you like a onion gravy, add some onion powder, even heavy handed with the onion powder, although a strong onion gravy really just goes with beef.