LeBron James, Los Angeles Lakers
Even though LeBron James is going to be 40 years old by the midway point of next season, there aren't many signs of him slowing down. LeBron is still one of the best players in the NBA and is the driving force for the Los Angeles Lakers as they continue to try to build around him to win another championship.
With a player option for next season, there's a belief around the league that LeBron is likely to opt out of the final year contract in order to secure one more big payday with the Lakers. At this point, I'd have a hard time believing the Lakers would want to move on from LeBron. In the twilight of his career, similarly, I don't believe LeBron would want to start over with a new team either.
The Lakers and LeBron simply seem to make the most sense for each other right now. The only thing that could perhaps repel LeBron away from the Lakers is if they're not willing to give him the big money deal he's likely going to want this offseason. However, I don't believe that is likely to happen.