There is a lot of talk about using quality at bats vs stats (avg, ops...) as a goal for hitters. I like the QAB thing but imo they reward passivity too much, like half of those categories are about not swinging (long AB, walks, surviving several pitches with two strikes...).
Thus I like a goal that is pretty simple: hit two balls per game decently to hard. With that I mean at a decent angle (say 0-40 degrees estimated and at a decent exit velo so no choppers or pop flies).
There is actually some numbers behind that. I looked at statcast data and tried to filter for decently hit balls. I used as a cut off 90 mph (slightly above league average) and -5 to 40 degrees. That is about the upper half of batted balls in terms of quality (median to top of the scale).
The league batted almost. 600 on those balls who go from average to really good and eliminate all the below average to bad hit balls.
2 balls of that fashion per game thus means 1.2 hits per game statistically. In 155 games that is about 185 hits which is a .310 average in 600 ABs.
That means that if you hit two balls per well you statistically should hit around or above 300 at the best levels. I think that hitting two balls well per game thus is a really good goal for hitters. Now you can't really quantify that but if you say this involves anything from a hard one hop grounder (that doesn't touch the ground until it passes the pitchers mound and doesn't take a second hop before it gets to or past the fielders, to most liners to deep fly balls (where the outfielders have to move back some and ideally to the warning track or short before that depending on the age group - say like 270+ feet for HS players ) an experienced coach or player should recognize that.
I feel that goal is motivating and not easy to do but attainable for hitters. It gives the players an aggressive target and not a passive one like don't swing at bad pitches. Now you want players still to take some bad and borderline pitches early in the count but the reason for this should not be because of the pitch count or getting walks but because borderline pitches are usually hit worse and by taking them you get another chance to hack at a fat pitch. Don't let any fat pitches get through. I started to coach this year some hitters and I find many are too passive.