You do NOT know how to go on the defensive side of things yet. Quit playing +5 all the ^&$*(&^@# time!
I trust you've already followed tj's (& my) advice to move everyone other than Spratt, Johnson & Morris to -2. After that, since you are mid-way through the season, you can re-assign distro based on efficiency. To me, that matters less than learning how to develop players (how to assign practice and get them the PT they need).
For instance, while you are finishing up the cupcake portion of your conference schedule, start Dudley in place of Cave. Just flip-flop their places in your depth chart. Just remember to re-adjust your depth chart when the conference tournament starts. Dudley is an offensive nothing, but he will actually be your starting PF or C next season and the PT will help his WE get up off the floor. He should, virtually, only be practicing conditioning, rebounding, defense & FT.