TBH I think the overly infatuation with "balance" in MMOs is what killed the old school feeling of MMOs to begin with. The need for balance causes the developers to have over arching control over the tiniest details of the game. And in order for them to save themselves work, they simplify things. That's why Yoshi-P says that he won't implement more choices for job variation because in the end he believes people will pick the best one. Well that's not really the point is it? The point is to create an environment where people can experiement/play/test builds.

For example MOBAs
LoL and any moba game has a lot of balance issues because of the many many choices to build your character(hots is a bit of an exception). Sure the game is never truly "balanced" but does that keep people from playing the game? Last time I checked it doesn't because MOBAs are the fastest growing genre still.

So I don't buy the argument of balance. I think its bad design philosophy and complacency.