That ending was pretty clever. I like how you have to do the non-obvious thing to beat the boss and get the good ending. It also works well thematically; the game is about the player character's greed, but you beat it by being generous.
The jump feels pretty floaty and awkward. The game isn't strictly a platformer, so it's not the worst thing, but it would have been nice if it felt better. Another thing that didn't feel great was how quickly you lose all your health when you touch an enemy.
Took me a couple of tries before I figured out that the checkpoint was a checkpoint. The fact that it's to the left of where you start that area means I never touched it by accident, and it didn't look like a checkpoint.