We've been doing the same grinding quest since lvl 76-90 for our lvl increase. Honestly to obtain lvl 99 I really hope SE has some plans of bring back the Maat/Battlefield type fights for us to increase from 95-96. It could even pertain to everyone's storyline for each job, and of course the fight wouldn't be up against Maat. Maybe a new NPC of some sort introduced into a continuation of your job's storyline or even yourself maybe mirrored somehow through another dimension(Wings of the Goddess,Abyssea,A Shantotto Ascension,Void Watch) we all know it's possible. I just really hope that come time to increase to lvl 99 we aren't stuck just handing over 20 merit points and some crests and doing another mini-game. Come on SE it's the final stand, to our last lvl's please let it be something similar to the G5 fight!! On a much grander scale of course.