Great feedback! Thank you so much!
Regarding "the deck resets after each battle?", the short version is it doesn't. Played cards go to the bottom of the deck, and new cards are drawn from the top. I DEFINITELY should've telegraphed that better (or at all). I wanted to add animations so you could see what each card did and where it went, but I had to cut that for time.
That's an interesting idea about trick-taking. I hadn't considered that. I had an inkling the player should have more control over what gets put into play, but I couldn't think of an elegant way to do it. It's nice to have that assumption validated, and that sounds like a good thread for me to pull on. It might also work well with some other risk/reward stuff I wanted to implement but didn't get around to.
Thank you again!