Ruby (Lucy Lawless) is interesting and all, but she's still sort of a grey area. While grey got a little more black towards the end of season one, when it was revealed that Ruby was the author of the Necronomicon and wanted to lead the forces of evil as a sort of "Godfather" figure, she's still not on the level of, say, Evil Ash in Army of Darkness. No, Ash vs. Evil Dead needs a recognizable antagonist, someone who fans can point to and say "that's the big bad," to borrow a term from Buffy. Whether it be for season or series, this big bad needs to be the focal point for Ash and company, and the source of all the deadite badness in the show. Otherwise, the show risks having things spiral out of control.