Isn't face Shaman pretty good now?
It is fairly good. Certainly in a better spot than face hunter right now.
Keep in mind, EU and NA metas are different. Here in NA it's a fine line between face shaman and hunter, but I think hunter still has the advantage, as long as they don't experiment with stupid new cards.
I only bother with one Mysterious Challenger. Two is ridiculous, but it's like putting two of the same Legendary in your deck when it's not something you tend to need two of, like Deathwing or Reno Jackson. Quartermaster, why bother? The Muster + Quartermaster + Horse Trainer + SHR type fever dream is something less valuable than other Paladin decks at the moment.