Good to see you are doing well.
Quite a bit of new content has been added. Not sure when you last played, but they added 3 new epic versions of dungeons; an epic pcave, spider den, and forest maze. They aren't all that bad if you know what to expect. Still can easily die if you aren't careful. More recent developments have been the shatters, which is pretty challenging. You definitely need a good group to run these. The event that has a chance at dropping the shatters has also been added (The Avatar of the Forgotten King). The event itself isn't all that bad, but things can easily get nasty, especially in the last phase with the blobombs. I believe they even made the avatar a bit easier in the most recent patch, because there was some issues with stacked shots that could instantly kill you.