If you haven't realized it yet, maple syrup and ham were meant to go together. The sweetness of the syrup perfectly offsets the smoky, savory flavor of the ham. And when you add a few other goodies in there, such as Dijon mustard and warm baking spices (as in the recipe below) you truly have a thing that hits the mark of perfection. It cooks in your slow cooker, which means there's not a ton of work.
Some people like to add whole spices to the slow cooker such as full cinnamon sticks, whole cloves and full peppercorns. An advantage to the ground varieties is that the flavor has a chance to totally infuse the meat. In addition, they are a little less expensive. Because the sauce is boiled quickly at the end, it also means no straining. Just pour everything into the saucepan and let it go to work.