Well, it makes no sense to refer to what was midgame in 2006 when it currently is 2012, just like you wouldn't call level 25-30 midgame when the level cap was 75, even if it was midgame when the cap was 50.

Actually, when you're about lv 60(and that is most certainly midgame), there is a lot of stuff you can actually do without raising your level even further. You can start doing your AF quests, for example, which offer somewhat interesting storylines in some cases. You can quest a lot of scrolls, you can do a lot of missions without needing help, and you can probably get past all the promyvions. You can unlock a lot of the advanced jobs as well.

It's not the game's fault that people wait until they are level 99 before they start doing these things. People just usually do it when they've hit the cap because it's easier.