I agree, health reaching 0 should not be something that results in a game over. I think a better way of handling health is that it should stop the player from doing runs because their health is too low. In the beginning of the game before the xeno on the ship, the character has to perform tasks that would heal the player, and consequently lower corruption values. But if you interact with the xeno to many times, the med bay used to heal the player will instead heal and corrupt the player as a result of the mixed DNA (or something similar)