How to end it all

Last night, I finished watching the fifth season of Dexter.  Now, according to that fountain of knowledge known as Wikipedia, a sixth season has been given the thumbs up.  It also states that this won't be the last, leaving room for a seventh, which probably will be the last.  So, with a possible end date in sight, let the speculation begin.  I had an idea going where he'd be in yet another game of cat and cat-like mouse, this time with Astor.  Unfortunately, that doesn't look quite as likely now.  The obvious solutions would be to either kill him off or have him pardoned for his aid to society.  There is a third option of him losing all ties to "normality" in Miami and finally does that runner he keeps trying.  Of course, I'm rather partial to an ambiguous ending like Angel (I don't count After The Fall, although I follow Buffy Season Eight) or The Sopranos (I don't care what you say, that was a great ending).  Let's make this interactive and you tell me your theories.