Her +1 ability is excellent against many opponents, and at least slows them down if its not able to kill anything
Haste is one of Magic's most common mechanics, dating way back to its very first set
While I'm not a Facebook guy, I know people who have very good luck buying collections from either friends or various Facebook groups
Of course, the real joy of the set is how easy it is to onboard new players
Regardless of this, Yawgmoth remains a powerful draw option for Aristocrat Commander decks, which got a significant buff recently
There are a ton of dream scenarios where it survives on turn 2 and you get to do something super fun with it, but the decks that will probably break it will probably be decks that run Solitude or Leyline Binding