I agree with July fourth.

There's no point power training slow improver's/trainers. Concentrate on players close to the level of star rating your aiming to improve them too and allow the rest of your squad to improve naturally from games and normal training.

I took the exact same decision as you have with my squad, last season, and stopped looking to buy players and just improve the fantastic squad I had assembled over previous 3 seasons. So far i have stared up three players 5-6* in the first week and I have got another 5 waiting to move up to 6* some time this week. All achieved through rigorous training schedules and using green packs to recondition my players before and after training. Purely buying new scout players every season is just to expensive and with no guarantees with getting the players you want or need. As the scouting lists are so bad and negotiations are all but a useless exercise for transferring players.

Personally I think its the only way to play the game. If you look to improve by investing in tokens each and every season it will cost silly amounts of money to stay competitive every season. Basically i Invest every 3 seasons and improve the the players purchased in the 2 seasons in between.