For the role of Alice I would cast Ariana Grande. Ariana is a young and fresh actress. She has had two main character roles on Nickelodeon as Cat Valentine on the shows "Victorious" and "Sam and Cat." I believe Ariana would make the perfect Alice because of her bubbly and youthful personality. Her character, as Cat Valentine is much different from her normal personality. I think she could play the role of Alice because she is very good at changing her voice and personality.