We need to brainstorm something high concept to figure out how the terrible horror
can continue.
How about
the human/dalek hybrid process somehow resulted in a virus that starts transforming citizens of the Big Apple into a new race of hybrids that must be stopped. Naturally, the altered DNA instantly (in that incredibly bullshit "my DNA travels via electricity!" manner) gives them every personality trait of Daleks, even though they retain their human memories.
Mayor Fiorello H. La Guardia is turned into a Dalek hybrid in 1934 and secretly starts building a giant skyscraper which is really a massive Dalek shell. Four years later, it is almost completed, and the Doctor must convince the largest Weeping Angel ever to exist (...yup,
) to fight it in a battle for the future of New York, America, and the Universe.
Wow, the shit just writes itself!