Other than scaling somewhat badly, Grift suffers from being a strong Engine counter. If your opponent is building an engine, you can Grift engine pieces (BM+draw will get to 7 kinda early), and then enjoy the stream of coins headed your way. At the same point, the engine player can't counter this since you're not really playing actions. Actions are fun, and making it bad to play them is a risk, design-wise.
I suggest making the bonus happen on any player's gain, and reducing the cost to a more affordable price (something you could open). It makes it really similar to Invest, but recognizing fast-burning piles is a cool skill, and coin tokens are awesome enough that even a couple of them can make a game. And an early Grift can net you 10 coins, which is still very cool.
I think this also would make it very similar (identical?) to another fan Event which was floating around.