Squads dont really win the Premier League trophy, strategy does . In fact Leicester won it years agp by having only decent squad if you compare them with most top teams in Premier League. For this season, its hard to say which team is really going to win the title because only 8 games played so far out of 38 games in total.
At the moment, there are only small differences in points throughout teams on the 1st to 6th position and one mistake would literally slip them away from getting top position on the league
Some new players are definitely needed to fit in the team. Otherwise the strategy wouldnt differ much from last season which is why some team insisted on bringing new faces or else they wont improve further with the same squad