One of the big issues with LOST, and this, of course, is my own opinion, is that it is continually being driven away from a character dependent plot. Originally, LOST essentially meant characters that were lost in their own lives and how they coped and experienced rebirth (Flashbacks are indicative of this). However with the introduction of flash forwards it seems it's a mythology push from here on out. You can only pump a character with back story so much.