I actually wish I had the resources to gather slow motion video from the side of players swinging, and could sync it up with the moment the pitcher released the ball.
I have this idea that the location of the knob of the bat could be tracked pre and post pitch release on takes and swings to determine things like:
1: exact depth of bat load
2: when the hands start/stop moving backwards in relation to pitch release
3: comparing takes vs swings to determine a batter's reaction time
4: exact time between initial forward movement and contact with ball
Gathering all that data on hitters would allow for determining if a slow/long swing is due to pre-pitch load (fixable), post-pitch load (fixable), physiological delay in pitch recognition (probably not fixable), or a lack of the fast twitch athleticism required to quickly swing the bat (perhaps fixable to some extent with specialized training).