I seriously doubt SE is gonna be buffing BLMs by any significant amount. Believe it or not, SE is actually smarter than 95% of the the player base so I'm sure that they are well aware that such a buff will create major imbalances. But who knows.

Anyways, I've heard that Yoshida said that they were not really "buffing" BLMs, they are making changes to jobs, and not just to BLMs. He even said that a "buff" to BLMs will likely create imbalance. He did also say that their goal is make it so no job will be preferable to any other job in any way (which is impossible really). It does worry me though, if that is their goal then their goal is make every job exactly the same except perhaps in play-style. Maybe that's what people want though?