It's very ironic that Paul Pogba is returning to Juventus for free. Six years ago they made 100 million Euro from him, now they got him back for free. As Pogba is still in his prime, I consider this a very very good signing. He will receive an annual salary of 8 million Euro. It's pretty normal for a player of this level. Pogba, who couldn't find what he wanted in Manchester United, can win championships in Italy again.
Pogba returned to Turin and will be part of them again. This time, he joins them as a star player, not a young player like his first time there. After signing a contract with Juventus and meet their fans, Pogba rejected to sign on a skirt of Manchester United. Awkward player in my opinion. At least Manchester United is the club that grows him up.
Angel di Maria also came, Juventus is much stronger now. They can go back to their good old days.
Di Maria will be a good player on bench and good substitution for Juventus when they need him. Juventus in recent seasons have good transfer strategy with star players who are free agents. From Pogba, Pirlo, Ramsey, Di Maria, etc. they are trying to get as many free agents as possible. They can have good contributions and don't cost them anything from transfer market.