Thanks for playing and providing some valuable insights!
Yes, the final tower is the hardest stint in the game. The puzzle can be a real stinker coupled with the fact that the endgame party seem to be a bit powderpuff as you alluded to.
My intention was to get people stuck thinking a bit at the puzzle, wandering around and obviously getting into fights to power up but I can well understand if that gets a little frustrating after a while :|
I put a focus on weaving the roguelike elements into the gameplay to provide the bulk of the experience and it makes me happy you appreciated the fog of war, sigil mechanics around the permadeath and careful resource use but ultimately the game is in dire need of a flesh out and tidy up, especially when it comes to narrative, player direction and general balancing overall.