
Increasing your decksize hurts your mulligans, but being able to pick your cards in the draw phase negates the issue of diluting your deck pool with extra cards. Essentially, this card allows you to pick a lot more of those niche, great-in-one-situation cards, and then toss them aside for your normal good cards if that situation doesn't seem likely. Enjoy the power of Fine Clothes in Carcosa and when the Parleys aren't in the scenario you can shunt em. Have Roland bring Handcuffs to the dance and toss them right back in the trash where they belong when the tentacle monsters come out to play.
Notably you will draw your weaknesses faster since the rate of draw is higher than the rate of deck dilution, and in that highly improbable and inevitably Arkham fashion you can draw two of them at a time (which then leads to a choose and discard situation, which assumably means you keep them both).
Also notably, your upkeep phase will take longer than everybody else's and you'll have to make a higher amount of choices each round, a situation that is all fun for some players and sheer decision paralysis for others. But if you're up for that enhanced complexity, this is a permanent that gives you a higher quality draw at the expense of a slightly lower quality deck with a more inconsistent start. If you're taking the rounded approach, this card is perfect, and discard synergy and interaction make it more so. If you need a particular start: Tarot, key assets and signatures, weapons of choice - this is more likely to be a pass.