If you guys want to get better, spend more time on a HARDER machine. Time spent on a machine like BSD or BK2K will help improve your reflexes much faster than playing on STTNG.
Stop trying to cradle the ball for every shot, but instead work on feeling the flow of the machine. As for multiballs, don't feel like you have to make a targeted shot with each ball. It's fine to attempt a shot with one ball, while juggling the others, don't have to hit a jackpot with each ball of a multiball!