Suns forming a defensive identity?

Phoenix ranked No. 24 in the league last season in defensive efficiency, giving up 105.7 points per 100 possessions. Fast-forward to this season, and the additions of Eric Bledsoe and Alex Len give the Suns reason to believe that the team's D could improve. What other changes are in store under new head coach Jeff Hornacek, who continues to emphasize that side of the ball in training camp?