"What makes her, just because she’s his creation, any more important than any of the companions who have come before her?"
Because she is the current companion. And Steven Moffat wants to write this story now. Why junk a great story just because the BBC can’t afford (sadly) to bring Elisabeth Sladen back to life? That’s what TV scriptwriters do – they write as well as budget/resources/availability will allow. Hell, maybe it would have been cool if Ace had been the companion to whisper that stuff into the Doctor’s ear – and maybe she would have been if the episode was written in 1987 – but she wasn’t and it wasn’t. Moaning that it was Clara instead is kinda biting off your nose to spite your face.
So what you’re really suggesting is that Moffat should have denied us of a story that’s been loved by the majority (looking at voting on a variety of sites) just because Clara was his creation? Maybe, but I’m glad he didn’t.”

SFX writer Dave Golder response to criticism of ‘Listen’ (x)

except that this storyline was perfect for clara - not just because she’s “an important companion” but because she has proven herself to be extremely warm and loving with children - any of the companions could have done the same, but that’s not the point

(via e1evenc1ara)