Looking good so far! I played through a session and once I figured things out, had a good time and made it to the final boss. The art is distinctive and stylish, and the transition from music to victory jingle is pretty clean no matter what part of the song it starts at.
Right away though, the first thing I wanted was a tutorial. I'm still not sure what the numbers on the bottom left widget mean except for the center one, which is the total number of cards in your deck. It's also pretty short, all things considered. Size settings (small, medium, large) would give additional control over how long a game is on top of choosing how to navigate the board... and speaking of the board, I feel like the free spaces should do something. Maybe you can backtrack through them, unlike enemy spaces, and/or they heal you by 1-3 points the first time you pass through. Long-term it'd also be cool to see different "worlds", or even a "Challenge"/"Adventure" mode where when you beat the final boss of one world, you start in a new, harder board of a different world with your deck intact, and at some point there would be a real final boss. For the "card shop", it might be useful to have a feature where you can pay to randomly re-assign the connections on a card you already own, ex. if it has one connection on the bottom, it's changed to have one connection on the top or one of the sides.
I look forward to seeing where Staff Only / Only Ruins Remain (?) goes. I'm on a deck builder kick lately and this one really caught my attention.