It is a huge expansion and the developers clearly put a lot of work into it. I never played EQ1, but from what I’ve heard/read of it, RoK will bring a lot of the flavor of EQ1 back – particularly with gaining faction with various groups.

The game, IMO, is suffering for having to support 24 classes. The T8 fabled set armor were largely cut-and-paste copies of each other, and the set bonuses some classes received make little sense for raiding – which is the only way those armor sets can be obtained. With fewer classes, the developers could concentrate on making the classes more distinct, and could perhaps actually learn how all the classes are actually played.