I thought the season ending wasn't too bad. It wrapped it up pretty well, came fuck all close.. like plastic sheet thin close.
I would have preferred Lumen stick around, but we all knew it wouldn't happen. That's the problem with the season long guest stars, especially with an actress like Julia Stiles. Despite opinions on her, she's a fairly known movie star, so I wasn't expecting her to stick around. (although showtime is getting William H fucking Macy on his own show...)
Sure it didn't end on a high emotional point like Season 4, but 4 was an outlier in that regard.
With Lumen's darkness "leaving" at the end, I'm wondering if maybe the show will attempt to go full circle and Dexter delves more into his so called creation with the goal of getting rid of his dark passenger as well.