I think they're finished with dlc with regards to this particular game. As said before there isn't much in the way of trials to be added, which leads me wonder what else they could possibly add to this game. The only things I can think of that they might possibly add are a couple of new weapons or perhaps a short side story to expand on one or two things from the original story.
However, before anything like that happens, I would much rather see all the bugs and glitches fixed. Although, the likelihood of any of the above actually happening seems low.