there are objective measurements for playing time. I've been involved with baseball the last 18 years at every level. Some coaches welcome all of the parent help they can get, but they have objective measurements involving ERA, WHIP, batting average, OB%, quality at bats, etc. where those measurements determine playing time. When starters have weak numbers, bench guys get x number of at bats or innings replacing the weak players to see how their stats stack up. That way, it's not the HC or dad coaches playing favorites. Always allow the numbers to drive playing time and you won't have a problem.

For several years while I coached youth baseball, I told all of the parents that batting order was simply in order of batting average (NOT on base percentage--never wanted to encourage walks). I also disregarded errors in the field to avoid subjective decisions. Worked beautifully and never had a parent complaint. They all knew that if they wanted their kid to move up in the order, he had to hit! The numbers were on Gamechanger for every parent to see.