Delilah + Flynn: Well she certainly sounds like the type of person Flynn would go after to prank on purpose, not that he would ever admit that. Haha. But it sounds like fun and I'm totally down for him pulling some sort of prank on her then trying to act all innocent about it afterward.
Indira +Eoin: Yes, I can imagine many people will get annoyed at Eoin about what he thinks about magic despite the fact he appears to be very good at it with very minimal effort. But a friendly rivalry sounds like fun, especially if she also wants to be top of the class. Something Eoin is aiming for as well simply because he has always had immaculate grades and doesn't want that to change.
Felix + Jingyi: Yes more friends before Hogwarts the merrier as far as I'm concerned. And it sounds like they would totally get along getting into mischief together.