I find cupcakes to be one of the toughest cake orders to do, not because of the actual cakes, but because of the frosting.
Simply making frosting is relatively easy, but working with a client trying to match a frosting that they like and that will apply to their theme is a whole other animal. I try to stay away from food coloring for frosting because if you add too much, it can compromise the flavor. However, if you add too little, you probably won't get the color your client wants. Cupcakes can be beautiful and flavorful if done the right way. But of course, there will always be those tricky clients who want dark blue frosting for their birthday, but if you know anything about me, you know I will always welcome the challenge!