If you make your own marshmallow fluff, which is essentially a meringue with some boiled syrup added—two things change. For one, you can omit the gelatin, so your yams stay vegetarian-friendly. (I always feel bad when the vegetarians can’t eat the vegetables at Thanksgiving)
You can also add in other flavors. I use this recipe from Epicurious as a base, then tweak it with mix-ins. Freshly grated ginger, for example, adds a nice hit of spicy fresh flavor, offering a counterbalance to all that sweetness.