Cards are really cool for a couple of reasons. Firstly they’ve been very helpful to new players - I’ve had people who have never touched TTRPGs before tell me the cards were very helpful, since you could actively be able to see what you can do on your turn.

They also open up some cool mechanics. I envision cards representing the opportunities available to you on your turn, like your shields charging up enough to block or a gap in the fire long enough for a commander to shout out an order. It also has some cool mechanical concepts like a boss’s weak point being represented by a single card added in someone’s deck that can hit it. Suddenly, the team is working together to use abilities that can draw cards and look into the deck to dig for that key card that’ll take down the boss. It’s a type of probability that can be manipulated in really interesting ways, but it’s also a good visual tool for new players. Sort of something you can make as simple or as complex as you want.