Unlike the Daleks, their menacing creator hasnt been overused in the slightest; in fact Davros has thus far only featured in one new story. The time is ripe for Davros to return (in series 10, though, along with the Daleks eventual return) and wreak more carnage. Russell T Davies has stated that he didnt kill Davros off and he left his ending ambiguous because he didnt want to be the person to kill of such an iconic and integral character. If and when Davros does eventually return Julian Bleach just has to portray him. His turn in The Stolen Earth/Journeys End was in a word, sublime, and it was very easy to believe that Davros was as deranged as he was touted as. Davros return should see the Daleks needing him for something, rather than confining him to the basement. Davros is integral to the Daleks history so we need a story to cement that notion. We need to see Davros as the leader of the Daleks, perhaps orchestrating a plan to restore Skaro in a similar manner to Gallifreys return. That way the Daleks would be able to return en masse and be a formidable threat to the Doctor again. Imagine both Gallifrey and Skaro returned to their original power. Skaro wasnt destroyed in the Time War but it was left ravaged and devastated perhaps some form of terraforming device similar to that which was used in The Doctors Daughter could restore its former state. This in turn could initiate another Time War, one which would result in dozens of stunning episodes.
