House chat mute.
To help combat cheating in exams, there could be a command added which makes the students unable to see or talk in house chat. This would stop the students from being able to relay answers to each other in mass groups and provides a fairer result.
Rictusempra edits.
When Harry is duelling Draco in the 2nd book, Harry uses Rictusempra, the spell is described as, "A jet of silver light". Maybe the spell should be turned gray from purple. And be a tier two spell, as it is introduced in the second year.
Swearing.
Whenever a player tries to swear in global, it gets changed to one of the insults from a whizzbang.
Brooms.
Making brooms with no damage and maybe having a little name on the broom with the models name near the handle or variants per broom.