I just finished this show today! Season 8 was likely the weakest season of the show, and the finale while I wouldn't say outright horrible, but certainly wasn't great. I am seeing people say they had less pre-production on this season than other ones? It shows. The final episode's greatest sin I don't think is that it feels more like a season finale than a series finale. I think that the idea behind the ending (that Dexter destroys the lives of those he loves and everyone he touches is better off without him) was much more strongly symbolized in the finale to season 4 than 8. In having Dexter unrealistically survive that hurricane, I felt it underminded the entire symbolic point of the ending. But, season 8 was filled with rushed plot points and poor logic on Dexter's part.
I am also rubbed the wrong way that of all the people Dexter leaves his son with, it is a wanted fugitive. Would have made more sense if they both were raising Harrison since love was blinding him to that end, but to leave her as a single mother to Harrison? Not crazy about that.
The final 3 episodes of this season felt mostly like filler, also. How many times can Saxson escape being arrested or fleee his home? How many times can Dexter enter a room to kill him? It just went on too long, and they didn't have enough plot to fill the episodes. It all felt so raw and messy. This disappoints me since season 7 was one of the better season, I felt. My favorites were probably 4 and 1, but 7 was a stronger one. But, alas, mistakes were made with how they ended the series.
This is an A+ show, with a Cish ending.