If Quidditch were a real game with the rules of the Harry Potter universe, the optimum strategy, given the extremely high value of the snitch, would be for everyone to be seekers (If allowed by the rules; I am not a Harry Potter expert. Even if the rules didn’t allow, having everyone act as seekers while nominally holding other positions would probably be what actually happened).

It’s not a very balanced game, needless to say.

As a corollary, that would mean that most teams would be nearly all girls, as they tend on average to both be lighter and more flexible, meaning they would on average also be better flyers and snitch-catchers.