You know the reason I think half the people want a female rival and or female league winner is to give Ash someone to ship besides the regional girl each main cast has. I think some want a strong battler female but others just want to see a love/hate relationship with Ash or both. I'm not saying everyone wants that, some probably really do want to see a strong female represent, but I'm sure a large number of the people demanding a female rival just want to see a shipping love story. If that is the case I say just stick with the boys. They get shipped with him anyway XD
RIP anime version of Glovehead. Pokemon Adventures will save you.