You have 1000 students playing sports at your school???

Find that hard to believe. Perhaps you meant you had 1000 students WANT to play sports?? And keep in mind that you have the same number of teams and sports as most other large 4a schools so there is no way you have more athletes than the two Fort Mill schools even though you have more total students.

As for boys vs girls. I think there are two factors.
1. I am guessing there is a higher participation level for boys so more boys playing rec. soccer and club soccer means more boys trying out and more quality boys for the teams. That also means more depth and less weakness when you have subs on the field and from what I saw on the girls teams depth is the biggest issue.
2. The boys game is different than the girls game. Far more athletic and at a much faster pace. I think this helps to even things out as well. I also think this means that the star boy players are far more impact-full than star girl players. So I think that evens things out as well.

Overall I think you see far more parody on the boys side than the girls side. The boys 4a state championship was a 17-8 school vs a 17-10 school. The girls side was 20-1 v 24-2. Also on the boys side there were only 5 teams with 4 or less loses while the girls side had 8.