This card is good as long as you have some way to break the symmetry. Notion Thief is obvious and I actually think this card is better than Mikokoro with Notion Thief as "Draw 2, discard 1, and the opponent discards 1" is generally better than just "Draw 2". You still net card advantage along with card quality and this keeps the opponent from building up some combination of cards to get out of it. Once the opponent is hellbent, you can realistically lock them out of casting non-instants by activating in the opponent's draw step, making it a two card soft lock.
Other ways to break the symmetry include running things like Deep Analysis (which is a reasonable inclusion with Dack Fayden), Worldgorger Dragon Combo, Delve Spells, Crucible of Worlds (discard land and replay it). Even without one of these, you get first crack at casting spells you would draw, which was a subtle advantage most people did not realize back when Brian Kelly and I were having fun with this card in various humanstorm builds. The problem in all of this is that Gush crushes strategies like this - they simply draw too many cards too quickly for incremental card advantage engines to be really viable in this metagame.
So great card, wrong format, is my impression.