Arrigo Sacchi always said attitude/character always first ("prima l'uomo, poi il giocatore"), and that's the only way how current Milan can restart his way back to the top, and he's damn right.
Just look at our season: We have more or less the same players like last year but got rid of some who were rumoured to be troublemakers wherever they play (Menez, Balo, Boateng comes in my mind).
We got players who seem to have a very good attitude which is also under everyone eyes in matches (Lapa, Gomez, Pasalic - even Sosa is trying). The rest of the squad already consisted of "good guys", even if they are not the most talented one (not even in Italy).
However, we agree that this team is more or less the same like last year.
Now look at the difference, the results, the way we play, the way the team unites the most everytime we are in trouble. Obviously the chemistry on and off the field is better than any time before in the past 5-6 years before. Even some players like DeS or Abate publicly admited that the group is way more united than before also because some players went away who didn't gave their all both in matches and training.
Even if Aurier was the best RB in the world, with all that well documented shit he pulled of (massive lack of respect towards coach and teammates and then the prison stuff), we should keep him the most far away as possible from Milan.