I really hope she doesn't graduate yet, not only would it spell "disaster" for MM, but possibly for herself as well.
Taka's an amazing singer and a great dancer, and her personality is definitely shining through more, but I don't think she'll be able to hold her own yet. I say 'yet' because who knows? she may very well become a great soloist in the future.
one major factor would have to be her personality. I mentioned it's opening more, but not enough as of yet. Gocchin, Aya and Nacchi all have their own set of dynamic personalities, besides being such amazing performers.