Once I figured out the combat system I expected to get bored as it's fully-deterministic, but I kept playing and I'm glad I did. Despite the combat being more puzzley than a typical roguelike, I died several times to groups of late-game enemies. I felt motivation to upgrade my character even though I knew technically the game can be beaten by repeatedly solving the puzzles, as I wanted to protect myself against my own tactical missteps and to reduce the number of puzzle repetitions. Once I got into a nice rhythm with the combat I came to enjoy its predictability.
One issue with combat is that it took a while for me to get confident recognizing which tiles were safe to stand on each turn, as it seems the tiles where an attack is telegraphed and the tiles where you can stand aren't lined up.
Nice touch with the random encounters with people who won't let you pass if you're not "green" enough. I never did figure out what to do there but I assume it has something to do with the tree...
I got the "good ending", so I'm intrigued as to what I could have done wrong to get the "bad ending".