if i was you, i will use a method that i've read from @Toxcatl posted
get only 3 FT and train them until 120% each season, and repeat every season for another 3 FT.
and at the 4th season, you will have full squad that you trained from the FT players with the oldest player is 21 yr/o which he still can be improved further.
but, you are the manager of your team, you make the decision..