Funny that you say that you like card games. While I was playing this my YuGiOh brain was going off lol
It's cool to hear the thoughts that were behind the scenes, so thanks for the reply.
Unfortunately, I think the last level I was able to get to was the one where you have no starting hand (level 5 I believe?). Turning a top-deck war into a level was funny, albeit even more luck dependent than it already is. (I don't know if this joke will mean anything to you, but I wasn't expecting to Chaos Emperor Dragon'd in a Touhou fan game, so I thought it was funny even though I lost because I didn't draw enough attack cards lol)
I don't think it's necessarily a problem that the character cards aren't super balanced. (Though things shouldn't be so incredibly under or overpowered still, like Marisa.) Due to the nature of the game, you simply aren't always going to have the opportunity to get the best things. Which is fine because these kinds of games are meant to be played multiple times and give varying experiences. While I haven't played it myself, what I do know about games like Binding of Isaac is that, because the weapons/items you get are random, you'll sometimes have to make due with stuff that you wouldn't normally use. Which can create novel gameplay scenarios.
For example, there was one point where I felt that the best character card to pick from early on was Youmu. Which was an interesting ability to try and plan around using.
I definitely felt the inspiration from the Touhou endings. It was a good touch!