Retaining all of them - particularly Johansson - will, no doubt, be a difficult task for Sweeney, who also has three high profile restricted free agents (Brandon Carlo, Charlie McAvoy, and Danton Heinen) to take care of this summer.
"I think you have to have the balance," said Sweeney, who was allowed to begin talking to UFAs on Sunday. "I think you have to have the depth in an organization and be able to match up in a bunch of different situations against a bunch of different teams to even give yourself a chance…we'll have an identity.
"It's hard to teach courage, it's hard to teach speed. [The] hockey sense piece is another area, so we're trying to identify them, as every team is trying to identify those same things. We had a good team this year and it showed."
Here is a closer look at all of the Bruins that will become free agents on July 1:
Unrestricted Free Agents
The 27-year-old has become an integral piece of the Bruins' fourth line over the past two-plus seasons, teaming up with Sean Kuraly, Joakim Nordstrom, Chris Wagner and ex-Bruin Tim Schaller to form one of the best bottom trios in the National Hockey League over that span.
Acciari, listed at 5-foot-10 and 205 pounds, has been a relentless force with his hard-hitting style (he ranked 18th in the NHL in hits with 221) and heavy forechecking ability. He also produced a career-high 14 points and eight assists in 72 games in 2018-19, while adding another four points (two goals, two assists) in 19 postseason games.
"We've had conversations with Noel and his representative just like we were with all of our guys. We'd like to see Noel come back," said Sweeney. "He'll have options, so that'll be up to Noel to see whether or not he feels that this is still the right fit for him. We value Noel as a player, for sure. He's kind of a bit of that fabric of that identity group in the bottom part of our lineup.
"He's made himself into a real valuable NHL player, so he'll have options with either us or elsewhere. You're never going to question his courage, for sure. He puts it all on the line…he plays with his nose over top of the puck and not everybody does that."
Acciari, who grew up as a Bruins fan in Johnston, Rhode Island, said he is going to take his time as he goes through the free agency process for the first time in his career.
"This is new to me," said Acciari, who just finished up a two-year $1.45 million deal ($725K AAV). "I'm not sure what to expect. Gonna take my time and look things over. Boston's been my home my whole life. I guess we'll see what happens."
Ultimately, the forward said he loves the culture of the Bruins dressing room, which is all he's known during his three-plus seasons in the NHL.
"I'd love to come back to Boston," said Acciari. "I love these guys, love everyone here. This is all I know so far. But we'll see what happens going forward. I can't predict anything…I'm looking for a family and these guys are my family.
"Great locker room, great coaching staff. Boston has it all. I'm a local guy - I've lived it and it truly is a special place here."
Video: Noel Acciari discusses his injuries and his contract
The 28-year-old was acquired from the New Jersey Devils at the trade deadline for a 2019 second-round pick and 2020 fourth-round pick. Johansson's tenure in Black & Gold did not get off to the smoothest start, when in his fourth game with Boston he suffered a lung contusion after taking a heavy hit from Carolina's Micheal Ferland.
Johansson missed roughly three weeks, before returning for the final six games of the regular season. Overall, the winger picked up a goal and two assists in 10 games with Boston, but it was his impact during the team's run to the Stanley Cup Final that defined his time with the Bruins.
The Sweden native was one of Boston's most consistent forwards during the postseason, combining with Charlie Coyle and Danton Heinen to give the Bruins a high-impact third line. Johansson finished the playoffs with 11 points (four goals, seven assists) in 22 games.
"This experience has been unbelievable," said Johansson, who just completed a three-year, $13.75 million contract ($4.58 million (AAV). "Coming here, this group of guys and going to battle with these guys everyday has been unbelievable. I've got only good things to say about everyone in here. It's been special…we'll talk and see what happens, if we can work something out. It's been an unbelievable place to play and I really loved it."
Johansson said that in addition to finding the right deal, he also values what will be best for his family.
"Playing somewhere where you feel good, you're happy, your family is happy, like it has been for me, that means a lot," said Johansson. "That's something I value a lot too. Hopefully we get to talking soon and we'll see what happens…I really love it here and it's definitely a place I could see myself staying."
At the NHL Draft, Sweeney said it was his intention to speak with Johansson's agent, J.P. Barry "shortly" about a potential deal.
"With the RFA side of things that we have, [there are] some things we need to clarify internally before I can definitively tell him," Sweeney said during his end-of-season press conference on June 17. "We found that Marcus was a really good fit for our hockey club. I was proud of how he got injured, came back and elevated his play, was really invested, thought he fit in really well with Charlie…gave us some options on the power play, was a really good fit. Good person, great teammate and got us to a certain point. Wish we could've finished it off."
Video: Johansson discusses his time in Boston
The veteran blue liner made his return to Boston in early September when he was acquired, along with a fourth-round pick and conditional seventh-round pick, from the New York Rangers in exchange for Adam McQuaid.
Kampfer, who had played previously with the Bruins from 2010-12, was an important depth piece on the B's backline, notching six points (three goals, three assists) in 35 games.
The 30-year-old played three games during the postseason, stepping in for a game each against Toronto, Carolina, and St. Louis. With McAvoy suspended for Game 1 of the Eastern Conference Final against the Hurricanes, Kampfer filled in and scored the game's first goal in the B's 5-2 victory.
"I thought it was awesome to be back. I love the city of Boston," said Kampfer, who was on a two-year, $1.3 million contract. "I made a lot of great friends here the first time, made even more the second time. It was great to be here, great to be back wearing the Spoked-B and go on this run with these guys."
UPDATE (6/25): The Bruins signed Kampfer to a two-year contract worth an annual cap hit of $800,000.
Video: Kampfer talks special season
Other UFAs - Zane McIntyre, Mark McNeill, Lee Stempniak, Gemel Smith, and Jordan Szwarz
Restricted Free Agents
Teams have until Wednesday to extend qualifying offers to their restricted free agents, which allows them to retain the rights of players whose contracts have expired but haven't yet reached unrestricted free agency. The RFA interview period begins on Thursday.
"I think the RFA market is one that's going to require patience on everybody's behalf," Sweeney said at the NHL Draft. "It just seems what's going around the league, we're not the only team that's going to have to probably see it this way."
The 22-year-old blue liner is coming off of the strongest season of his young career, during which he paired with Torey Krug to form Boston's second defense pairing, which was a force during the Stanley Cup Playoffs.
Carlo has used his size (6-foot-5, 212 pounds) and strong skating game en route to becoming one of the league's best pure shutdown defenders. His plus-22 rating was the 12th-highest in the league in 2018-19. He also notched two goals and eight assists in 72 regular-season games.
The Colorado native was a star during the postseason, the first of his career after missing the last two postseason with injuries. Carlo picked up two goals - matching his regular-season total - and two assists in 24 games, while ranking second in plus-minus (plus-10) behind only Zdeno Chara.
"I love it here. I love the city, I love the fans. I like you as media people," Carlo said with a smile. "But no, it's fantastic. I can't imagine myself playing any other place. This situation has just been a blessing for the past three years and I hope to experience it for many more."
As of the Bruins' breakup day on June 14, Carlo said talks of an extension had not yet picked up.
"No, not really," said Carlo. "Throughout the year there were slight things mentioned at times…I'll kind of let the agents handle that portion of it. Just know that I want to be in Boston for as long as I can."
Video: Carlo talks season, contract situation
The British Columbia native has been a dependable two-way forward during his first two full seasons with the Black & Gold. Heinen has played mostly on Boston's third line but has performed well during stints higher in the lineup, particularly a stretch with Patrice Bergeron and Brad Marchand while David Pastrnak was out with injury in March.
The 23-year-old had 34 points (11 goals, 23 assists) in 77 games during 2018-19, a dip from his rookie season when he ranked fifth on the Bruins in scoring with 47 points (16 goals, 31 assists).
Heinen joined Johansson and Coyle for the B's postseason run and contributed eight points (two goals, six assists) in 24 games.
"I love this group," said Heinen. "The young guys, we've got a couple years under our belts now. The older guys make it so easy on us coming in and have done such a great job of leadership-wise, bringing us along and teaching us the ropes. I love this group and it's probably the tightest team I've ever been on."
Video: Heinen looks back on the season
The Bruins hope that McAvoy is their stalwart on the back end for years to come. After debuting during the 2017 Stanley Cup Playoffs, the Boston University product has continued to develop towards becoming the team's No. 1 defenseman.
McAvoy has played alongside Chara on Boston's top pairing for the majority of the last two seasons and has been a workhorse, contributing greatly at both ends of the ice. The 21-year-old led the Bruins in time on ice (24:30) during the playoffs, while chipping in two goals and six assists in 24 games.
The Long Beach, New York, native missed significant time during the regular season due to injury, but still managed 28 points (7 goals, 21 assists) in 54 games.
"I don't want to go anywhere. This is the best place on Earth," said McAvoy. "This is home for me now. I live here in the summer. I just love it here. I want to be here forever. I think losing in the manner that we did, I want to just win so bad, just to be a part of it, to join a city full of champions.
"Everyone here is a winner at one point. Just want to join it so [freaking] bad. We were so close. Just have to believe we'll be back."
Sweeney was pleased to hear that McAvoy has a such a positive view of his adopted hometown.
"You certainly are proud of your players, and he should be proud of himself being a part of the Boston Bruins. For me, that's what you want," said Sweeney. "You want players that are invested, that are really good teammates and that are really good, and Charlie checks all of those boxes.
"And I think he recognizes that the people around him, that were in the locker room, that we were able to put together, checked them as well, and that's how you end up having success."
Video: McAvoy speaks during end-of-season media availability
Other RFAs - Peter Cehlarik , Ryan Fitzgerald, and Jakob Forsbacka Karlsson.
UPDATE (6/26): The Bruins announced that they've extended qualifying offers to RFAs Brandon Carlo, Peter Cehlarik, Danton Heinen, Ryan Fitzgerald, Jakob Forsbacka Karlsson, and Charlie McAvoy. Gemel Smith was the lone player not to receive an offer, making him a UFA.