I think this is a fair and balanced counterspell, and I am not a counterspell fan in the least bit. It is strictly inferior to the original in two ways: first is that it is 3CC, second is that it does not remove the target from the deck (which can be turned into advantage, but 90% of the time it will be a disadvantage).
Tangential, in the past 2 blocks blue's power/semi-brokeness has not been due to counter, it has been a two-fold problem tied into:
1) Unbalanced mechanics. Of the newest mechanics that they've introduced to the game, they played right into blue strengths and/or they gave blue the best cards for that mechanic. Exmaples
* Affinity: Thoughtcast, Broodstar, Qumulox, Hoverguard
* Madness: Great pitch engines (Carefull study, Merfolk Looter, Aquamoeba), and Wonder...
* Storm: Mind's Desire
* Artifact Synergy (besides Affinity): Artificer's Intuition (this card WILL become a problem), Trinket Mage, Fabricate, March of the Machines, Thirst for Knowledge (which I adore BTW)
2) It will always have the best card-draw. The straight card advantage will always ensure that blue is played in constructed. That is the real problem, but I guarantee the card draw will never go away.