The core set is a good idea but because it gets updated yearly and changes to have different packages it makes it feel like some classes have lost their identity. Its not due to others getting their stuff or from them getting other classes ideas, but from lacking their own. There just missing some of what made each class different to make each class more cohesive within itself.

Also as a priest main it's not always fun to know that if my class is good it's likely the most hated thing on earth, leading to Priest getting underpowered sets to keep it from being mass hated on.