I'm an old player and I feel like there are so few damaging spells compared to before (I might be wrong). Something I would love to see be added is the Dolohov Curse, a high damaging spell that I believe should be a lvl 80 spell as it was created by a death eater and not taught at hogwarts. It could be like sectum sempra and expecto patronum where u have to do some sort of challange to get it or just make it a graduate spell. It could take a lot of mana and be hard to cast, but a high risk high reward type of spell for skilled duelists to use.