1.Under her "gruff" exterior, Prof. McGonagall is an old softie, really.
2.(answering a question about Dumbledore)Although McGonagall is a worthy second in command, she is not Dumbledore's equal.
3.(talking about new contents in Pottermore)The background on Professor McGonagall, I’ve had for years and years and years, and I think I always thought it would have somehow found its way into the story and it just never happened. Harry and Professor McGonagall just never had an interaction or a conversation where that would plausibly come out, so I was left with this life story of this character I liked so much and nowhere to put it. Now I’ve got somewhere to put it. That was so satisfying.