Magic Johnson revolutionized the concept of point guard and established a whole new set of standards on how they are evaluated, an all-purpose point guard who is extremely tall for the point, able to run the fast break and finish, shooting, driving and especially passing. Eventhough he did have good success during his career and since I'm old school, the guys I've listed below immediately came to mind. They played in a different generation of basketball and during a period when the NBA was just blooming into a league where, as Uwe said above, there weren't many teams in the whole league. But when these guys played, they were the focus of their team and ruled the court from the point. In no particular order:
Bob Cousy, Boston Celtics (I agree with Uwe)
Oscar Robertson, Cincy Royals (comparible to Magic in his day)
Walt Frazier, NY Knicks
Nate Archibald, KC Kings
Jerry West, LA Lakers
I started out with nothing and I have most of it left.