Awesome work there, I like how you gave her leg articulation similar to what Toy Biz once tried with their Madame Web figure! I would prefer those, and it would save Mattel some costs.
Good solution for the cape. But I wonder if it could work and look better if done in sofrt plastic. Toy Biz tried that with their Mandarin figure, but it was messed up in production and the gown was produced too thick.
I still wonder if Mattel could legally modify MYPs Horde Wizards into a female form and release it as "Shadow Wraith".