concentrate on a bunch of trainne 3 for single position training, or 5/6 for two position training. Sell sometimes 1-2 of the trainee, and buy quality in the other position from that money + the visitor income.
Starting to switch the training every week betwenn front and backcourt isn't good, because young talented player always have an value for beeing young and talented in the weeks you don't train them they loose value - which means you loose money you paid for them when you get your trainees.