Juventus draws an image far from the years when they dominated the Italian League. This is because, as you said, the quality of the squad is now below the league level. They need to mark the transfer period to return to their old glory days. Maybe the Pogba transfer would be a way to do that.
Juventus must prioritize the defensive area, especially the left-back. Juventus also have to find a midfielder with physical strength who can dominate the midfield, and of course they also have to find a replacement for Paulo Dybala who chose to go to another club.
Juventus must build a team that is able to compete in European competition, so far Juventus has always been a champion in the Italian League, but difficulties in Europe, the last time Juventus lifted the trophy in European competition was in 1996.