safe cracker is the most known example of this, which is kind of polarizing.
losing a ball where you have x number of balls is so universal that most find timed play confusing. perhaps more of a ball save mechanism where you can see what is happening would be better? i.e. a Pierce Bronsan Goldeneye like dick flinch to throw the ball back in play or maybe something more mechanical like Silverball Mania?
-c