My friend Neil, thank you for the wonderful digitization of Rowling's world. This work turned out to be unbearable even for professional game publishers.
And precisely because I liked this job, I can't close my eyes to some disadvantages. And I'm not talking about the upcoming additions on artifacts and familiars (their absence is not such a problem). And it's not that there are no inserts with the history of Hogwarts and the Ministry (everyone knows this from books). The matter is different:
1) There is no characteristic digitizing the friendliness or talkativeness of the character. (In DnD systems it is charisma, in DH it is sociability, in WoD it is manipulation). It is important for social throws to determine what effect the character's actions had on the NPCs.
For the world of Potteriana, "Compassion" would be suitable. This is the very characteristic that brought Harry Potter closer to his friends and what Tom Riddle was completely deprived of (which, by the way, can explain Tom's failure in the selection of supporters and, as a result, defeat).
2) There is no opportunity to play as a child of a magician and a magical creature (Half-breed), for example, a half-giant (Like Hagrid) or a half-goblin (Flitwick). Of the weirder ones , we can recall the half - veela (Delacour). We need to think through the mechanics of special traits for these creatures and their children. (For example, witchcraft without a wand).
3) How are things with Lycanthropy? Are there mechanics for it?
4) Purebred families sometimes have a number of magical features that are inherited (for example, the language of snakes, ghost ancestors or contracts with brownies).
As well as diseases (for example, the hysteria of Gaunts or the quirks of Lovegoods). How will this be digitized?
5) There are no mechanics for divination and predictions. It would be useful for the master to be able to give players hints in this way.
6) There are gaps with magic herbs. So in book 4, Gillyweed played a significant role. We need to digitize those of them that had a magical effect.
7) There is no digitization for the cores of magic wands. In your game, it is not clear how the unicorn hair differs from the phoenix feather...
If you answer these questions, then your game will become much more complete and suitable for masters and players. Sincerely, your potential player.