If we're picking apart things we'd like different in the HP books, I don't care about Ron-Hermione-Harry. However...
The Wizarding world attitude to physical injury & potential death (especially children) is shocking. The hazards of Quidditch are shocking. Their safeguarding sucks.
Snape is openly abusive to many children; why was this allowed?
Why are Slytherin so awful? Do they have know noble selfless heros in the Wizarding world at all?
Dumbledore's partiality to Griffindore house is shocking.
That rich kids could openly flaunt their wealth & power to other kids in front of teachers: I guess this fits with how 1920s schooling in England would have worked.
Thank goodness for Newt Scamander because until he appeared, Hufflepuff seemed utterly eternally useless. The huge message was only Griffindores & Slytherins were powerful magicians. If you went into another house you must be completely lacking in talent, aspiration or motivation. Know your place.