I don't think series like Heroes and Dollhouse play very well as a weekly series. There are too many interconnecting plots and too many main characters. I actually enjoyed Season 3 of Heroes but I rented it and watched it over the course of a week. None of the episodes of these series are very good as stand alone shows, because it is hard to have a story for each episode along with the continuing storyline.
Shows that succeed in this way have only one or two central characters- 24, Fringe, X Files.
I'm not sure how LOST fits into this theory, except maybe that The Island and the mystery are actually the central character, and the people are secondary.