Idea - Instead of Sanity a boolean value, make it a integer. Lets say it is from 0-11. So, if the number is less than 3, kerbals are sane. If its between 3 and 6, kerbals will do something else, lets say boredom. 6-8, can't EVA, time to maneuver and control the pod is slower. 9-10, kerbals wont control craft at all. 11. They die