Remember, save up your gold and only buy the new packs - when the nerfs hit, you'll be able to disenchant for full value. And the nerfs will hit.
Also, Iron Juggernaut isn't that great except in the control mirror, at least theoretically. If you're aggro, you don't want them to be living long enough to draw loads of cards, plus it costs too much for something that doesn't IMMEDIATELY change the game state like doomguard. In the control vs control, it'll be great-ish, but I don't know if it's better than say, Sylvanas. REALLY strong against miracoli decks.