I have already seen people say the card is too good for Modern by making it too easy to interact with the board, while I think that slower Midrange and Control decks finally have the chance to interact with your opponent, which is the best thing which could happen to Modern in the long run
If you are playing a fair black-based deck, then Mage is your go-to guy against Abzan
The second ability this card comes with is called Let's Have At It
I think, though, that this can be achieved in a way with less feel bad, and less impact on the stores that might miss out on single sales
Bump its power up to maximize the stax-effect and all but guarantee you draw when it triggers
If another player is instructed to touch your library while you are a card, communicate with them to follow the instructions safely and comfortably