Well I am yet to see Keys,have good footwork and controlled power on her shots for a whole tournament, especially a GS tournament,anyone with variety in their game,eg can use slice to 'disrupt a power hitter' also bring forward to the net,to see if their net play is up to the task.Regarding Sharapova,players usually hit in her strike zone,she was not a good lateral mover especially on her fhand side,that was one sure way to bring about UFE in her game,her second serve was weak,also prone to double faults.