I appreciate the honest feedback. This is my first attempt at making a card game and its still very early in development. I mostly wanted to put a demo out there to see if the basic game was fun enough to play to justify continuing to work on it. My hope with this game is to eventually have a passable slay the spire clone with some unique mechanics and a good balance of adult content. But its just me working on it and it's definitely not there yet. So I'm glad to hear it was at least stable, playable and you'd like to see more from it. That's what I was hoping to hear : ).
I'd agree with most of your points about things that are missing, something like a relic system I had planned to add but ended up prioritizing other fixes and didn't get it into the demo. I also liked some of the mechanics we came up with like cards that play next turn, so I'm glad you found those interesting.
With how the demo works right now, namely a single run up to the first boss, there's not much use for relics anyways. You've set your priorities in a sensible manner such that the most basic features come first. It was indeed fun to play once and see what this game has to offer, but it didn't leave anything open for a possible second playthrough. Continue adding content and features and I'm sure it'll get there eventually