sell all ur 3* players u will find 3-4 * players next season which are better of ur oldies 3*
Keep the fast trainers or good perfomance 4*
Keep the 5*

In my opinion do not renew any contract tha ends now (except 6-7 * if u have ,and very good 5*
You will find better players next season and for 3 years,not 2.

good luck