This could be a great move but they need to be careful. Reverting a card like Yogg would be super cool but I think bringing back pre-nerf Raza could cause issues in Wild. I suppose they can always make changes and revert it again if smoething gets out of hand.
Looking through the list of nerfed cards no longer in Standard there aren't many I would revert. Something like Spreading Plaugue is fine at 6. Maybe Small-Time Buccaneer or Bonemare. But most of the nerfs were warranted and necessary at the time.
One of the cards I'd like to see un-nerfed is Ancient of Lore. Even though it's still in Standard it's doubtful the card would even see play right now with the current power level.
Raiding Party would be the best unnerf of the handful of rotating nerfed cards. Kingsbane pirate was not the best deck, yet it got a double nerf due to standard.
Possibility they finally rotate the classic set, or maybe they just hof some of the nerfed classic cards that are effectively banned out of the game. It is a joke to consider mana wyrm or cold blood playable given the high power level of standard sets anymore.
Raiding Party with (3) mana was very strong in combination with Preparation which discounted your spells by (3) mana. So you could play Raiding Party in your first turn and equip Kingsbane afterwards. As Preparation now discounts your spells by (2) mana, this card combination will never be as strong as before.