The final episode, were you disappointed ? You are not alone. When you think of the history of Dexter it is not unreasonable to to expect some sort mega blood fest, but instead we get Dexter still alive, ready for reincarnation in a spin off series.
My hope was Dexter himself should get his just desserts, be slaughtered in the same fashion he used to employ, and Debra gets to live happily ever after raising Harrison. However the producers decided on a flat ending banking on someone who will invest in a new show in a new location. Perhaps they are right to look after future revenues but it is not as exciting and thrilling as a mega blood fest.