While I'm not a huge fan of MMO games I recently seen some screens for Star Trek Online and they just blow me away. The game looks stunning and the enviroments look really rich in detail and atmosphere. The only MMO experience I have was Tabula Rasa which I played for a couple months before I found out it was doomed.
Take a look at the screens yourself. They just look stunning. To me anyway.
Official Website - https://www.startrekonline.com/frontpage
No released date yet but it has peaked my intrest