It is all about the Daleks. I am a sucker for Nazi allegory. It comes from me being such a World War II buff.
They have certainly been overused, particularly in the Russell T. Davies years, but they still possess the sense of menace that keeps them as formidable adversaries after all these years.
I am not too fond of the new rainbow army of Daleks that have emerged in under Steven Mofat--and I even liked the cult-like, mutant Daleks created by the emperor for “Bad Wolf/The Parting of the ways”--but I am holding out hope thecae is not permanent. Go back to the beat up, brown and black scheme or the retro gray color for the future!