I recently just came back as well and the biggest thing that stood out to me was the jump in quality of the content. Dropping the ps3 was the best thing they've ever done.
Alot of Episodes came out since then, latest is Justice League Dark Which includes a new way to get the OP back item. Kind of like artifacts. Augments and Artifacts, you can read about them here: https://www.dcuniverseonline.com/guides/dcuo-augments-guide-2018 https://www.dcuniverseonline.com/guides/guide-artifacts-dcuo Water Power is the latest power that came out at 2017, Universal messaging system is about to come with GU95 and also they revamped the tutorial. I wrote about the Universal Messaging System here: https://dcuosgothamgazette.site123.me/news/news-universal-messaging-system New tutorial before the Universal Messaging System update: https://dcuosgothamgazette.site123.me/news/test-server-new-tutorial Note these are on test but will come to live servers at some point soon, We had GU94 a week ago I believe. (you can always save the gazette for news and guides ) Hope it helps!