Just finished the first 13 chapters - you have a fine story here!
Ollivander as a mentor is different and interesting. You write their characters well and the dialogue is just fine.
The underlying unrest and dissatisfaction with the status quo, as indicated by the interesting group in Ollivander's shop, indicates much interesting story to come.
Whilst I am enjoying the Katie/Harry romance, it has the feeling of impermanence to it, as if it is a "first relationship", rather than the abortive one Harry had with Cho. Is this the case? In a way I hope so, as the hints of something between Harry and Hermione really appeal to me.
Your subtle intro of bias, even in the well-intentioned Weasleys, was excellent, and I look forward to more on that too, and how Harry, Hermione and the gang deal with it.
Keep up the fine job!