Overall I think you are making a pretty good start for a first season in BB. You haven't overpaid for any 30+ veterans whose skills will soon be declining, so score one for you. Instead, your purchases have been solid, especially the 27 yo center Vitin Olivar.
Also, you've already jettisoned the deadweight players you were given at the onset, so you're not carrying wasted salary. 12-14 players is enough for managing gameshape.
Which is whatt you need to do better at (same for most div V managers). There's a huge difference in performance between players with strong and proficient gameshape, and those with mediocre-avg (most of your players). The key to this is to manage the total minutes per week your guys get, aiming for about 55-65 ideally (40-75 is overall recommendation). BAsically, if you have a guy starting in your league games, he probably shouldn't be playing at all in scrimmages. Don't even put him in the lineup to prevent the coach from inserting him.
For training, really it looks like Ben Terrell is your best trainee. Get him 48 or more minutes in whatever position you're going to train him, and try improving his various guard skills. If one of this skills is particularly low you might try training that, if not then you can never really go wrong training outside defense on guards. You might be able to get one or more guys trained along with Terrell. On your current roster there's nobody that screams "Train me!", but improving Bradley Koch or maybe Ru Haikun could improve them a bit (though you might have to play Haikun out of position). I wouldn't buy a new trainee now since it's so late in the season. Perhaps you can add someone in the draft to pair with Terrell for training? Are you investing in scouting points. When you do get serious about training, you'll want to improve your staff, advanced (level 4) is probably good enough at this stage.
Beyond that, investing a bit more money in your arena always helps.