GAMEPLAY: There seemed to be a lot of "unspoken rules" that made the game hard to learn. I still don't fully understand why I can't play some two-card combos in a day--I think it has to do with plants and animals? The discarding rules also seem strange, but I think the white rectangle is telling me something to do with that. At one point I had 17 cards in hand (so many they went off the screen), and I have no idea why. A full tutorial would likely break the atmosphere, but a dictionary of symbols accessible from the side or hover-over tooltips would be useful. While there's a lot of potential with the different card types, they don't interact with each other as much as I expected. I'm a big card game fan myself, and I could definitely see myself getting hooked if I knew what was going on (and once you add those extra cards like you said).
VISUALS: I got intrigued right from the start with the atmosphere, which helped push me over the learning curve. Bonus points for using Kablammo. The light grid and atmosphere effects kept things interesting without being distracting. UI could use some help--centering the hand, clarifying the meaning of symbols, nudging the action buttons into alignment, and removing the tangent between the cards and the text all come to mind.
SOUND: The music doesn't loop perfectly, which should be fixable, but the heavy lo-fi-ness adds to the atmosphere. Card thwips could be a touch better, but I like them as is.
THEME: I don't personally see it, though maybe because I've played other card games this jam that went further with the cards themselves (like eating them for bonuses).