For some players, a few talents are under-tuned or not interesting enough. Since the number is not large, there will be not much difficulty to replace. The talent trees still have traps for the unwary. For instance, a Fury build that skips over Raging Blow is making a serious mistake. That may seem obvious to current players but it’s the kind of thing someone returning to the game after a hiatus might not understand immediately. While there is something to be said for safe choices, it would also be nice if the talents we expected players to have were talents they always had.
True hybrid builds are neglected by some players. To be fair, these builds were either not very competitive or were just cherry picking a few powerful talents in order to create something that was likely overpowered, especially in PvP. In other words, the reality of the hybrid build never lived up to the myth. But now it’s impossible to have a hybrid build, and we understand some players want them back. There are tough choices within the trees of many specs, but there aren’t very many of them within each spec.