It didn't feel like there was a reason to mix a shooter with blackjack. They didn't do anything for each other. Progress was pure luck because it only depended on blackjack and the shooting didn't do anything to improve or reduce winning prospects. Maybe having to shoot the cards or making the enemies the cards. Trying to stay alive while not getting over with shooting them or something.
But the way it was done it didn't feel like the concepts improved each other