Good deck, good guide, thanks!
I went with the Spellbreaker option, because there're to many annoying taunts out there.
I do not see it as OP because Skulking Geist is already kind of a default card against some decks and works here as well.
I'm one of the players which likes the mechanic of arena but do not stand a chance so it's very frustrating. Why not offer a free casual arena where you can win nothing but it also costs nothing but you can play and practice arena runs. And then if feel fit enough you can do a real arena run. I believe this way arena would not only be for arena pros and more people would actually play it (meaning the non-free variant).
I think they are worried that too many people finish 5 runs too quickly so that people with open Heroic Brawl runs face the same opponent way too often or find no opponent at all.
I took my some time to get Doomsayer out on turn 2 without him having either exactly 7 damage on the board or Confuse in his opening hand. But once I was past that it was a piece of cake.