I believe the baseballs that MLB uses is completely different than what is used in college and high school. The way that they are prepared is completely different than what you see in high school and college. This is what makes the balls slicker in MLB compared to what is used in high school and college. I believe the ball is also prepared differently in the independent leagues though I think MLB has been giving them some of their balls as these leagues have become testing grounds for MLB to implement some rule changes (pitch clock, moving the mound back, etc.). If you watch pitchers especially ones that don't use the current substances they will rub the ball to remove some of the substances that MLB puts on the balls to get a better grip on the ball. MLB just needs to figure out which substances to approve and which ones to remove from the game and it should help both the pitchers and batters. The sunscreen substance is probably the hardest one to regulate as all players are more than likely wearing sunscreen so you can't really tell someone to not wear sunscreen. If MLB told players they can't wear sunscreen the MLBPA would just sue and they would win as it is a health issue. That rule wouldn't last for more than a day if they did that.