I agree w/ what PastryPet wrote, maybe taking an art class to learn about color theories, artistic composition, how to recognize and use these.
I feel that is missing in your cakes/design. Without understanding these concepts and how to apply them correctly, it makes the cakes look very amateur- doesn't matter how smooth the icing may be.
WFCS, has these is their designs- and that is appealing and adds to their popularity.
Also, an actual class in person...