If you want to change the human form into one that includes animal parts then I think you need a MuCo (An) spell.
Remember, as a rule of thumb Creo takes something closer to its ideal state (including calling something that doesn't yet exist into existence). Muto effects unnatural change upon something.
Yup MuCo(An) would fit better. Unless you consioder anubis a more perfect form of a human being Make sure no priest is near when you discuss the implications of your theory
To Become yourself like a hybrid form would be MuCo (An) Range Part, but I give a Level 4 or Five for have natural atacks betters.
But if do you want have wings? Could be Cr(Mu)Co(An) for add wings and not transform your arms in wings? This is a question that I've haven for many time...