One of the best things we've done recently for my kid's hitting is found a former D1 pitcher in his mid 20's who throws him Batting Practice twice a week (for a very reasonable minimal fee).
My sons 2 travel coaches would pitch live AB's in the winter to the team indoors from regulation distance. Both old D3 players from a top level program. One was a righty and one was a lefty. They sat in the low to mid 80's and threw a great cb and slider. It was priceless practice. If you can't find that, look for a Probatter PX2 in your area. I would drive almost 2 hours both ways so my son could use one.