Rozier still has a role on this team, and it could be significant in terms of having a good shooter off the bench. He is not quite a point guard, and Larkin certainly has better PG skills, but there's a reason Larkin bounced around the league and played in Spain last year: He is very small, smaller than IT actually. Brown seems to be ahead of Rozier in the backcourt rotation, but it seems Rozier is still a better shooter than Brown. I am also a litte suspicious of Brown's defense; seems Batum was beating him consistently during he 3rd quarter.
Tatum is a 3/4 so I don't see him as taking any guard minutes from Rozier.