I’m going to address keeping seniors who don’t play that increase roster size. My son’s high school coach would allow seniors to dress for varsity senior year if they hung in there for four years. The writing (varsity playing time) was on the wall for these players junior year as part time JV players.
The coach told them they were invited to be varsity players senior year as long as they didn't gripe, their parents didn’t gripe, they cheered and chased foul balls.
A couple of kids didn’t take the uniform over chasing foul balls. One of the seniors was such a good kid he had the ability to be a team leader from the bench. The team went nuts when the kid finally got an at bat. He drove a triple off the fence a foot from being a homer.