I just hope she doesn't write any more Harry Potter after the encyclopedia. All good things must come to an end - I think she's ended this part of her writing career. I really don't want to see any more Harry Potter books.
Nothing can be as good as the first time out... too much of a good thing and all that. That was another reaction I had - I was kind of, maybe not angry, but worried that she left it open at the end, especially for Albus Severus. I don't want to see any spin-offs - it would be like a Disney movie sequel (those horrible things, those).
So while my first reaction was !!!! it kind of turned into, "Wow, I really hope she just drops this and leaves it alone, and moves on to other things."