I am sorry, but a lot of the content has been already destroyed. How many quests are challenging on ANY decent built at cap?
I find that slavers, for a quest, is decently challenging when I play a barb, or a fleshy kensei solo. I would like the group version to be challenging too, but I can't tell if it is because every freaking time I play in a group it is filled with warlocks, shirred spammers, shuris, and other OP builds.
Warlock is just silly as it is. So yes, it needs to be toned down. No, it isn't the most DPS in the game. But it is the single biggest easy button there exists.
I don't need reaper if we all hold a level of power that is adequate for content.
That could have been achieved boosting the innate abilities of classes instead of giving MP/crit enhancer/crit spell damage/PRR until the game is trivialized. Boosting songs, boosting some of the active innate abilities of monk, boosting the benefits of paladin to the party with auras, all those are examples of things that would have made the game better. More balanced, less DPS but more synergies, etc.
Warlock needs to be toned down. They need to rethink the amount of magic damage out there, and they need to stop creating this silly sameness to all the classes.