Preheat oven to 350F. Arrange a roasting rack in a medium baking dish and place turkey skin side-up on top. Season turkey all over with salt and pepper, rubbing underneath and on top of the skin. Set aside for a moment.
In a small bowl, combine softened butter, 4 cloves minced garlic, parsley, rosemary, and sage. Season butter with salt and pepper to taste.
Rub half of butter all over turkey breast, using your fingers to rub underneath the skin and on top. Scatter small garlic head, shallot halves, and additional rosemary sprigs around turkey.
Roast turkey breast at 350F for 1 to 1-1/2 hours (about 20-25 minutes of cooking per pound of turkey) basting 2-3 times throughout roasting with pan drippings until turkey registers 160F when a kitchen thermometer is inserted in the thickest part of turkey (do not touch the bone if using bone-in turkey)
Remove turkey from oven and brush all over with remaining half of garlic herb butter. Allow turkey to rest uncovered 20 minutes while you make the cranberry compote.