really cool stuff. I think you should have a bigger penalty for when the knight moves to a spot that can be taken by another piece.
the penalty could be relative to the value of the piece
I made it like that in the beginning (and wrote about it and other decisions in a blog post[1]), but felt it was too punishing. Maybe I could punish with 1/2 of the piece value.
[1]. https://rakhim.exotext.com/knight-ride-a-game-about-rogue-ch...