What’s the future for Jaylen Brown? Grant Williams? Brad Stevens and the Celtics have some decisions to make.

Jayson Tatum (left) said after the Celtics' Game 7 loss that the franchise needs to sign Jaylen Brown (right) to the super-max contract.Jim Davis/Globe Staff

Most NBA teams dream of attaining the level of success the Celtics have had over the past decade. They have been in the playoffs for nine consecutive years, reached the conference finals in five of the last seven, and made one NBA Finals appearance.

But in Boston, where legacies are determined by championships, the run has been encouraging yet unfulfilling. After they were walloped by the Heat in Game 7 of the Eastern Conference finals Monday night, the quest for the franchise’s 18th title and first since 2008 was pushed back yet again.

This team remains powerful, and most of its young core is under contract for next season. Now, president of basketball operations Brad Stevens must decide whether to simply tinker with the fringes of the roster or consider a more substantial overhaul.

The futures of Jaylen Brown and Grant Williams will likely be the Celtics’ top priorities. By earning All-NBA recognition this year, Brown will be eligible to sign a five-year, $295 million super-max extension this offseason.

That deal would briefly make him the highest-paid player in the NBA, a hefty figure for a player who just committed eight turnovers in a brutal Game 7 performance. If the Celtics decide that Brown and Jayson Tatum are not a championship pairing, they could look to trade Brown this summer.

But the 26-year-old wing will be on an expiring deal. It probably would make more sense for the Celtics to offer Brown the super-max and give him and Tatum more time to take the final step. If it doesn’t work, they could trade Brown in a year or two, when he would still have plenty of value and be under a longer guaranteed contract.

The NBA’s new collective bargaining agreement, which will go into effect for the 2024-25 season, includes some prohibitive measures for the highest-spending teams. Most notably, a second apron will kick in for teams operating $17.5 million above the luxury-tax line.

Teams that pass this apron will have limited ways to fortify rosters. They will lose the taxpayer’s mid-level exception, the most common route for an over-the-salary-cap team to add a key rotation piece. In trades, they no longer will be able to take in more salary than they send out. And they no longer will be able to sign players whose contracts were bought out by their previous teams.

Having Brown and Tatum on super-max deals almost certainly would push the Celtics past the second apron. It’s something Stevens will have to seriously consider. But it’s also true that All-NBA players do not grow on trees, and replacing Brown with a collection of draft picks or younger players now could force the Celtics to step a step back, even if only temporarily.

Grant Williams (left) is likely to be a restricted free agent.Jim Davis/Globe Staff

Williams, meanwhile, will likely receive a one-year, $8.5 million qualifying offer in the coming weeks, making him a restricted free agent. That would give the Celtics the ability to match any offer sheet he signs with another team.

Last fall, Williams was seeking an extension worth about $54 million over four years, but the Celtics’ offer fell short of that.

It was an odd season for Williams. He received inconsistent playing time but was generally productive when chances arrived. He made 45 percent of his 3-pointers during the playoffs, but was not used in five of the games, and the Celtics were 10.3 points per 100 possessions better with him off the court than they were when he was on it.

League sources have insisted that the Celtics intend to keep Williams, and the limited team-building options in the future should increase the urgency. But if Williams signs a high-priced offer sheet with another team, it could give the Celtics some pause considering the hefty luxury-tax bill that’s on the way.

As of Wednesday afternoon, the Celtics’ top brass had yet to meet to formally discuss offseason changes, but there are no indications that coach Joe Mazzulla’s job is in danger. Mazzulla took over after Ime Udoka’s sudden suspension last September and guided the Celtics to 57 regular-season wins — more than Udoka or Stevens ever did — and within one win of the Finals.

It was a frustrating finish for Mazzulla and the team, but the belief was that Game 7 would have unfolded differently if not for Tatum’s ankle injury, Malcolm Brogdon’s forearm strain, and Robert Williams’s game-day illness.

There is no question that Mazzulla’s coaching staff will be fortified, however, most likely by someone with head coaching experience.

There will be some reshuffling at the bottom of the roster.

Danilo Gallinari will likely exercise his $6.8 million player option after missing this season because of a torn ACL. A league source said the 34-year-old forward could have been cleared to return for the Finals, although it’s unlikely he would have been thrown into such a tough spot after the lengthy layoff. Nevertheless, it’s a good indicator that he will be fully ready in time for training camp, although the Celtics also could look to shed his expiring deal this summer.

Among players on guaranteed deals next year, guard Payton Pritchard’s future seems the most uncertain. Pritchard never cracked the regular rotation and all but requested a trade before the deadline. He has made it clear he wants to play, whether in Boston or elsewhere.

Forward Mike Muscala, who never secured a rotation spot after being acquired from the Thunder in February, has a $3.5 million team option, just slightly above the minimum for a 10-year veteran.

Blake Griffin, an unrestricted free agent, was a solid veteran locker-room presence and had some useful moments down the stretch of the regular season. Luke Kornet and Justin Champagnie are on nonguaranteed deals. Kornet played well when Al Horford and Robert Williams were unable to play on back-to-back nights and is a Stevens favorite.

Rookie guard J.D. Davison will likely return on a second two-way contract, but center Mfiondu Kabengele is no longer eligible to receive a two-way deal since it’s his fifth year in the league. The NBA is also adding a third two-way slot, so the Celtics will have two openings to fill there.

The Celtics do not have a first-round pick this year, but they are in position to get good value with the fifth pick of the second round, No. 35 overall.