3. TARDIS (Or Child Of The TARDIS)
Im not suggesting some brand new plot line to replace River, Im simply saying that she looked into the heart of the TARDIS, which no one has ever done. Even though the Ninth Doctor took the Time Vortex out of Rose, we dont know if theres any left over. With this in mind, we don't know what it/she could do if the Doctor was in imminent danger like he was in The Name of the Doctor and when he inevitably will be in the Fiftieth Anniversary. If Rose is the daughter of the TARDIS, is it possible that the TARDIS can call on her when needed, much like how Ten programmed a defense in Donnas memory? It would have to be an younger version of Rose before she got trapped in the alternate universe it would take too much time to explain otherwise sent over to tell John Hurt that the moment is approaching. The TARDISs number one goal is to protect the Doctor. If she has to call upon Rose or if Moffat decides to go plot-crazy, take her from the alternate universe and/or conjure up another Rose it would still make sense that Rose and the TARDIS have a connection from when she looked into the Time Vortex. It doesnt sound incredibly far-fetched when you think about it the only time weve seen Billie Piper as Rose is in the outfit she was wearing when Ten goes back and says goodbye to everyone God help me if were going to repeat that which would lead us to assume that Rose is going to play someone else, at least in her own mind.