That's the end of main story content. The Commercial District will be opening in 10.4, the next supporter release. I believe you get a message to that effect when you get the quest (at the end of The Hell's quest) but it can be easy to miss.
Ahhh crap I did blow past a pop up message right when I got the quest. Could not find a way to see what it was though I should have guessed. Thanks for taking the time to respond!
