I would like to see some other kind of horizontal gear grind, or item drop. Not a increase in stats but perhaps introduce something that is solely focused on PvE.
An extra defensive and offensive stat on items or armour that helps you against new enemies. A bit like how Agony was introduced.
Doesn’t HAVE to be armour or weapons, I would just like something that is a progression outside of masteries which also gives me the satisfaction of getting a new item.
Since they have mounts now a rare mount drop would be good that only appears in a new dungeon.