Both Butler and Leonard can become free agents during the offseason.
That was the second-biggest move of the summer following LeBron's decision to leave the Cavaliers and sign with the Lakers despite reaching four consecutive NBA Finals in Cleveland.
While there isn't another established star on L.A.'s roster, James will play alongside of stable of promising youngsters, including Brandon Ingram, Kyle Kuzma and Lonzo Ball.
The Lakers likely have enough to be a playoff team in 2018-19, but they need another All-Star to elevate themselves to championship contention in a Western Conference that includes the Golden State Warriors and Houston Rockets.
Butler and Leonard are two of the NBA's best two-way players, and either of them would make the Lakers a true championship threat.
The 29-year-old Butler is a four-time All-Star and four-time All-Defensive Team selection who has averaged 20 or more points per game in each of the past four campaigns.
Although Leonard missed all but nine games last season because of injury, he is accomplished in his own right with two All-Star nods, two Defensive Player of the Year awards, one championship and one NBA Finals MVP award to his credit.
Both Butler and Leonard are talented enough to be go-to guys, which may play into their reported lack of desire to join James.
Both compete at or near an All-Star level, but it can be argued that neither would have the same franchise-changing effect that a player like Butler or Leonard would in L.A.