i can add few more skills that will make biger diversity in rooster
Sniper-skill for mid players that will rather shooting than passing to attackers
Quicksilver-for def players, instead of kicking out after corners or free kicks he will rather long passed to attacker for counter
Robber-for atacking mid players and strikers that will making preasure in def players with ball and steal it for 1 on 1 against keeper before defender passing to the teammates

Also agree about player hardly can be a team legends if changing all team every 2 seasons..,like idea about using it as special trainer, but maybe it can be used as scout as well, giving him special orders what kind of player and with what skill you looking for and he search among young players in your youth team and in market for less tokens than
at normal scout report