The thing I've always loved about the seasons of Dexter is that there is always one main antagonist to Dexter. This season lacked that in a big way. There was just too many of them to have good closure at the end. I felt like it was scattered storytelling. There was Ray Stevenson's character, Hannah, Deb (in the beginning), LaGuerta, The Phantom, and then Hector toward the end.
It was definitely one of the weakest season so far and I'm afraid they are going to drag too much from this season into the next season. The Hannah situation probably isn't over, the LaGuerta situation has to be resolved and then they'll likely try to throw in another antagonist to spice things up. Not looking forward to it.