Hello, there are currently unlockable stats. Among them is a double jump.
The attack hitbox was out of range, which is why it felt like the attacks weren't landing. I fixed it yesterday. You'll see it in the next patch.
I love your idea for the cards. I've been thinking about how to implement them, and there will be two methods for now.
1. It will be through exploration. Find certain objects and you'll unlock a card.
2. It will be through "Achievements" - repeat an act X with an enemy.
I'm still thinking about how to integrate it. Thanks for your input. When I have the first card, I'll send it to you.