I agree with basically everything you said, the only thing I can see carrying over from this season to the next is maybe now Quinn is on Dexter's 'side' but even that is questionable since the writers seem adamant about not having Deb find out about Dexter, at least not yet.

The show is still fun to watch every week but nearly everyone I talk to, including myself, is getting pretty tired of the same recycled plot lines. Next season should be the last for sure.