They could consider the top 25 for each role in the rankings per data center. As in top 25 healer, melee, tank, and ranged class. This way it remains 100 across the data centers but promotes more usage of classes rather than everyone trying to heal or something since it gives the best chance at cracking top 100 given that the class has the most impact in matches. The job rankings is interesting but then you could end up being ranked on jobs like drk solely because you are one of only a handful of ppl masochistic enough to use the job in the first place.