With the combination Wendy's Amulet and Premonition, which forebodes every token and thus prevents Henry Wan to miss, you'll get on average 2.67 resources/cards on his action (with the starting-standard NotZ chaos bag). It is versatile as you can avoid the overdraw and choose what you lack most, even upgrade a Dark Horse deck; but it is unreliable, as you basically toss a dice to know how much you earn.
I feel like making his ability a trigger or even "when you are about to draw a card or gain a resource" would make it funnier and yet not broken.
Spending action for this effect feels wrong.