Free agents are useful as subs/reserves and they save money for 1st team players. If you buy young players, then buy only 5*.
If you don't pay for tokens and buy green and red packs to power train weak young player, then you should buy 5* players, they are more useful.
This is trophy archieve of my (2nd) club after 4 seasons
http://forum.topeleven.com/attachmen...ub-trophys.jpg