NEW YORK — It pays to be a center, whether you are an All-Star or a promising young Turk. Also, there is a lot of interest in a 38-year-old two-time MVP. And, the main domino has not yet fallen, although Monday will be a key day in the life of Deron Williams, the Brooklyn Nets and the Dallas Mavericks. One more thing: For the first time ever, restricted free agents rather than unrestricted free agents ruled the day on Day One of the