So the difference between Angel Food Cake and Sponge Cake from a cooking perspective is eggs.
Angel Food Cakes don't have egg yolks, nor do they have a leavening agent, baking powder or baking soda, nor do they have fat (oil or butter) in them. The cake rises because you have whipped egg whites and then fold them together with the dry ingredients.
Sponge Cakes have egg yolks, but also contain no leavening agent and very little or no fats. The leavening comes from beating the egg whites separately, then combining with a mix that contains the egg yolks combined with the dry ingredients.
Chiffon's are somewhere in between. Chiffon cakes are light like sponge cakes, but the egg whites are not beaten separately. Chiffon cakes also generally contain a fat, so they are more tender and moist than sponge cake.
Ultimately, all 3 types of cakes are Vanilla flavored.
So the my question to Scratchy is, do you want to taste the egg in your cake?
If so, go with the Sponge Cake flavoring...if not find a Vanilla flavored cake/cupcake/etc... that has less of a whole egg flavor to it.
If you are looking for that Angel Food Cake cooked in a Bundt pan then topped with Strawberries, you want less egg yolk and more of a just Vanilla with Strawberries in my opinion.
Hope all of that made
sense.