3. “Try out” is useless.
It’s not. Try out is not meant to be abused for every recruit, it’s meant mostly for those expensive backgrounds to prevent you from hiring hedge knight level 3 in early game as you finally managed to put together enough funds …only to find out that he has a wooden leg. Moreover it’s completely optional, you don’t need to use it if you don’t like to.
It’s also useful for late game if you hunt for particular traits. Like Iron Lungs.