Just to have one completed and "out of the way" would feel fantastic at this point... LOL. As much as they are my least favorite, I say Snakemen. Just get 'em done and then they ARE DONE. There are no other mini-comic Snakemen, no MYP-created characters from their faction... no Filmation... all that would be "left" would be repaints of the army builder pack if Mattel bothers with that. Plus, right now, King Hiss is a lonely fellow. If they could knock out the rest of them by the time 2014 is over, it would be kind of nice. A feeling of completion, or something.
But if I had my way, I would really want the Horde finished first. But there's so many of them left, and they're mostly unique sculpt characters... who knows if it's ever gonna happen!