Reggie, of course, also played for one of the most famous A's dynasties ever after they moved to Oakland. And Roger got to play in two additional World Series (1967-8 for the St. Louis Cardinals) after the Yankees were through with him.
Bob Cerv may have collected 50 or more additional home runs in his career had he played every day for a lesser team. But he could only play part-time in an outfield with guys like Joe DiMaggio, Mickey Mantle, Gene Woodling, Hank Bauer and Elston Howard.
The 1950s were the best era in Yankees baseball history save only the 1920s. During that era, Cerv still managed a respectable .278 batting average, but only 421 at bats during his six years with the Yankees (1951-6) and a .289 batting average and 1323 at bats during his three years (1957-9) with Kansas City in that storied decade.
Your account is true for Maris, but not for Jackson. Reggie was, indeed, a Kansas City A that followed the club to Oakland where he won Worlds Championships in the 1970s. Charlie Finley dismantled his team soon afterwards and traded Jackson to the Baltimore Orioles. When Jackson’s contract expired, he was granted free agency (something not available to Maris) and signed with George Steinbrenner and the Yankees that winter.
Reggie Jackson was never traded to New York.
Very difficult to hit .289 as a part-timer. Preparation and fundamentals are important to a hitter, but rhythm is also important. Hard to ‘go on a streak’ when you play once a week with a couple of pinch-hit opportunities.