While KdB is a talented player he's not an essential purchase, Sterling Kun and Silva as the front three, with Yaya , Dinho and Pogba?? behind. Nasri as back up for DS. Navas for Raheem. The two outstanding positions in the starting line up that need attention are CM and a LB.
If we get De Bruyne and he is ok to play on the wing, Silva can move in the middle behind Kun. I think most of us would agree that this the position where Silva should play. So with De Brunye we would not just add a really good player to our squad, we could also move our (in my opinion) best and most important player into his favorite position.