Stress testing servers would be better than PTRs. This isn't Blizzard that will nerf and buff something just because someone sneezed. Honestly, the team already has in mind how the classes are supposed to work. We see "balances" when the playerbase fails to meet the performance needed to play the class well (3.0 and AST). Very few classes get any balances, just tweeks (like BRD and making Minuet instant, but with a cooldown when it was originally a stance that took 3 seconds to cast like it was a song). They fixed the Raw Intuition bug pretty quickly.