5. Rose
Well, Billie's looking good isn't she? With her hair all a-curl and her eyes all a-glow but she's not looking very Rose Tyler. Rose was common. True she was brilliant but a shop-girl and that was the point of her. She wasn't unaware of fashion and style but she never looked quite like this except once. Cast your minds back to 2005, Eccleston has wowed audiences as an updated, damaged iteration of the Doctor; John Barrowman has put in the subtlest performance of his career as a mysterious con-man named Captain Jack and Billie Piper has surprised audiences with her surprisingly good performance as Rose Tyler. At the climax of this series Rose looks into the 'Heart of the TARDIS' and takes into her the power of the Time Vortex in doing so she gains power over reality, she can see all of time and can remove the Daleks from existence. I think this is the Rose that we are seeing even though she's not in the same costume (surely a time-goddess would have power over her own wardrobe) and she will be appearing to our characters in hallucinations like the mysterious woman (Claire Bloom) does to Wilfred in 'The End of Time' (Specials 3 and 4). Rose, like Clara will have been appearing to the Doctor, affecting his life and decisions using the power that she gained at the end of 'Parting of the Ways' (Series 1 Episode 13). The only interactions that we have seen from Rose are with John Hurt's 'War Doctor' in the trailers which makes me think that Rose assisted more in the end of the Time War than we had originally suspected...