My 12 yo went from 3 practice a week (1 for his school and 2 for his travel) to just once a week for the past 3 weeks. His team practice usually covers the warmups, BP, positional fielding/throwing and cut drills. I work him out with him 1x week for bullpens (following Driveline's youth program) (about 2 hrs). 4 to 5x a week of hitting, a few minutes on the tee then the rest front toss with varying pitch types/location and arm slots to work on timing and adjustment (~30 mins) with a few ABs in game situtations (ball strikes). We long toss 3x a week and those day also work on fielding (grounders and fly balls) and throwing as an IF and OF as he plays all positions. I try to get him at least 1x week dedicated to C drills (blocking and pop time). Luckily we are playing only baseball now so there is time put in the work. He is at an age where he understands the need to use different throwing mechanics for the different fielding positions and he still sometimes forget which one to use but the extra practices has significantly improved his fielding and throwing.
I know some may feel this is too much (my better half included) but he is the driver for this and school work is not an issue as he maintained great grades and really learned to maximize hisbday to include studying. The improvement is evident in games and it is the biggest motivator for him to keep being successful.
I am curious to know other people's training regimen.