At the very least, he'll need to play out the remainder of his contract and pick up his player options in 2014 and 2015.
Longevity is no small accomplish when talking about what a player has meant to his team. Alonzo Mourning played 10 seasons for the Heat in two separate stints. Tim Hardaway gave the franchise five seasons.
But more than any other player, Dwyane Wade remains the face of the Heat.
Beyond playing in Miami for nine seasons, Wade has never played for another club. He also helped the organization win its first title by averaging 34.7 points per game against the Dallas Mavericks, and almost single-handedly willed his team to victory after falling in a 0-2 series hole.
For what it's worth, Wade also deserves a great deal of the credit for assembling the Heat as we now know them.
In addition to passing on an opportunity to play for his hometown Chicago Bulls, Wade recruited James and Chris Bosh to join him in Miami. Whatever he does on the court, Wade's off-the-court contributions suggest he deserves a lot of credit for just about anything this team accomplishes over the next few years.
One of his recruits now stands ready to make this franchise his own—not just in terms of the here and now, but in terms of history.
It doesn't make a lot of sense to set a quota for how long James must remain with the Heat before truly supplanting Wade's legacy. This isn't about years alone, and if it were, Wade would always have the edge.
Nor is this merely about how many MVP awards he racks up or any other measurable accomplishment.
These are the kind of questions that are, by the very nature, debatable.
To start the discussion, though, there are a few things James probably needs to do besides sticking it out with the Heat for at least the next four years.
Spending the rest of his career in Miami certainly wouldn't hurt his cause, but nor is it necessarily a prerequisite. If LeBron goes to the Lakers when he's 38, he'll still be identified, first and foremost, with the Heat.
Winning another title under James' watch is, on the other hand, almost certainly a prerequisite to becoming the greatest Heat star of all time. Once again being named the NBA Finals MVP would seal the deal altogether.
It seems sort of unthinkable by now, but if the Heat win another ring while Wade is playing the team's best basketball, LeBron's mystique would take a hit. He can't be the best player in the world if he isn't even the best player on his own team.
Again, it's unthinkable.
But such a scenario also highlights the complexities of James' career going forward. It won't be enough for him to just win titles. He'll be subject to raised eyebrows the very moment he looks like Miami's second-best player—title or no title.
He could get away with being the team's second-leading scorer, especially with his penchant for triple-doubles and unfailingly filled stat sheets. He could even get away with returning the lion's share of ball-handling and play-making duties to Wade—though it's unclear why that would ever happen.
But James can't afford to start pressing. He'll get into trouble if he chokes at the ends of games or appears responsible for important losses.
That's the double-edged sword of being your team's best player. You take credit when things go well, but you take the blame when they don't.
It goes without saying that James will continue to be his team's best player, so the more important variable is that things need to keep going well.
The longevity will help, and the dominance will be a given. To replace Wade as Miami's all-time great will require another ring or two for good measure though.