That was fantastic! Your Rolanda is awesome, such an energetic personality and so independent. Love her backstory and her admiration for Amelia Earhart. What a great role model for Hooch!
With Minerva's tone of voice you capture the perfect voice of a (bookish, intelligent and ambitious) teenage girl (My dear reader is such a nice touch), but she's all the way recognizable as Professor McGonagall.
I also love the cameos of Walburga Black, Tom Riddle and Myrtle. What you did with canon was amazing. Wonderful job!