If they are going to insist on playing man to man they need to change things up.
They need to play a 3rd CB when Hamilton is in the slot- maybe Ambry Thomas or Brandon Watson - and keep Hill on Hamilton letting him follow him wherever he is.
They need to keep the 6'4, 240 pound McCray or 6'5, 250 pound Noah Furbush on the 6'6 Geisicki and let them get physical with him. Can't keep putting a 5'11 Khaleke Hudson on him- Hudson can't get physical with him AND he's giving up 7 inches to him.
And while I hate the idea of ever putting a LB or S in man to man with Barkley- if they insist on doing so they need to stop with Mike McCray and man him up with one of the safeties Metellus or Kinnel or one of the faster LB's like Bush or Khaleke Hudson.
This is just obvious stuff. I don't know why Brown hasn't adjusted sooner.