I always recommend giving yourself the extra day.
Whether you are flying or driving back home, I think giving yourself one more day in the homeport city after the cruise allows you to be able to fully enjoy the last day of your cruise. On top of that is also reduces any stress involved with the possibility of a late arrival or even an on time arrival with a slow debarkation process. Both of these scenarios are completely out of your control and if you plan ahead and give yourself the extra day none of it will matter.