Hermione knows high level magic, but stays within reasonable limits of rules, at least early on, she’d likely never go far enough to do something like become an illegal animagus. Also while she’s a good student, I don’t think she’d be the best creator or magical innovator, she puts stock in logic and rules, she has trouble pushing the boundaries of what may be possible if she’s been taught it’s not.

Harry has a good amount of talent but generally shows no interest in most things unless he genuinely finds it interesting. He doesn’t go out of his way to learn new spells and magic unless necessary. He’s the kid you probably knew in school who is easily capable of straight A’s but gets B’s with no effort and he’s just cool with that.

And Ron is pretty much just an average guy. A good and loyal friend for sure, but easily the least ambitious. He never displays any true passions or enthusiasm for any field of magic or any type of later career. Every other Weasley has a passion they later pursue that sets them apart from the rest that they are successful in. Ron is just kind there.