You need to think about replacing the guys who will be retiring soon, I would start looking for young free agents, since you don't have a huge budget... some you might sell, others you might use on your team. They will be in the tranny list with (F) after their price, I would find the slowest time on your server when people are asleep to avoid using too many tokens.

Training if you don't buy/earn tokens should be only the condition they have to where they will recover close to 99 by match time, or using greens you have earned/bought to restore and train more only on your faster trainers.