I agree... it has to run its course. I would like to see a defining moment to end the series. Obviously, we don't know what this new season will bring us, but if a deal is reached for a few more seasons, the fear that the creativity and quality of the show will diminish, will increase.I like the show but it has been running in place too long.
I'd like to see Dex get 'discovered' and see a final season that has no rules. Dexter the hunted. Perhaps a chase across country, I dunno. But something big and final.
I always thought this show would end with Dex in jail. An entire population of people deserving him. His last words to the audience would be "I'm free"
Knowing the MC Hall is negotiating a new contract means IF he renews the show probably goes for several more years. So a series finale is probably not coming any time soon.