MESA, Ariz. – On his walk from the Cubs’ hitting facility to the team’s clubhouse on a recent Arizona morning, Pete Crow-Armstrong was met by a group of six kids on the back patio of the complex. They scrambled over and lined up – a couple wearing his jersey – and the star center fielder stopped and signed autographs for each one. Crow-Armstrong has quickly put himself in the face-of-the-franchise...