I understand you think this can be solved by class balance, but it doesn't. The classes in this game is fairly balanced as it is, but that can not be said about the encounters. In 2.0 coil one was so heavily biased towards BRDs it was ridiculous and CT was biased towards Ranged DPS, making some parts almost impossible without them. Also, it is impossible making X classes that works just as well as the other ones for every encounter. This will lead to people not wanting certain classes for certain encounters and with that block the classes from progression. Image when there is more Melee classes. I am pretty sure people will still only want to take 1 melee solely for their LB.