I agree about a balance,but don't punish some managers because of the stupids tankers.
I started playing 22 april 2015 and my best player till today was a 7* at the end of a season.
Sometimes i stay at same only level because i don't have time to play,so yes,the season after i have a better team,but never a GREAT team and there is always another manager with a stronger team .
But to promote teams with 9* players.....or why not 8* it's a good idea,because i played once against a team with normal average but with seven 7* and 8* players between a lot of 3,2 and 1*