Making sure the new additions and diverse personalities mix together is new manager Ozzie Guillen, who is outspoken, colorful and yet extremely driven.
Still, for all the fanfare the franchise has made in recent months, their success on the field may largely be connected to the fact they're playing on a different field.
Being under a roof just might be what it takes to push the Marlins over the top.
After 19 seasons of enduring excessive heat and unpredictable rain at Sun Life Stadium, Marlins Park will offer climate control and comfort.
"It will be great," Marlins president of baseball operations Larry Beinfest said. "Just the uncertainty of rain delays and the stress associated with it -- pitchers getting warmed up or not warming up, waiting around, starting and stopping -- it takes a toll on players, physically and mentally. We know we're going to start on time and get through it. It's peace of mind more than anything else."
Wednesday marks the new beginning when Miami opens at night against the St. Louis Cardinals before a sellout crowd of 37,000 and an ESPN national audience.
Aside from guaranteeing prompt starts and cozy conditions, the Marlins anticipate the building will help boost up their win total.
"I don't think people realize how much of a toll [playing at Sun Life Stadium] took on your body," catcher John Buck said.
Buck signed with Miami as a free agent after the 2010 season. He was warned by previous Marlins catchers Matt Treanor and John Baker to prepare for a physically draining 2011.
"I got to experience last year what Treanor and Baker were telling me before I got here," Buck said. "To experience it, it's not that you feel tired, it's just that you go to push at the end of the year, and it's not there. Your bat speed lags a little bit, no matter how you train or anything. You play that hard in that much heat and that much humidity, it gets harder and harder to recover over the course of a season.
"Having that roof, and having that air conditioning and having that cover from the sun, it's going to be huge."
Will eliminating the rain and heat reduce injuries?
Reyes, who dealt with hamstring issues in New York, thinks so.
"No doubt. I think my legs are going to be more fresh, because I don't have to worry about cold weather or hot weather," said Reyes, who was limited to 126 games last year. "If it's going to be too hot, they're going to close the roof. I think that's going to keep me healthy for a long time during the season."
As a pitcher, Johnson said new ballpark will offer a refreshing change.
"You can't stay hydrated out there," Johnson said of the club's previous open-air stadium. "It's pretty much impossible. In the middle of the season, August and September, it's pretty impossible to stay hydrated that long. You can drink water. I'd drink water for like three straight days, and you're still dehydrated at the end of the game."
The roof gives the Marlins the best of both worlds. If the weather is nice and pleasant, the roof will stay open. But if rain or heat are an issue, it will take roughly 14 minutes for the roof to close.
"We're going to have more energy and not have any more games over 110 degrees," said Anibal Sanchez, the team's fifth starter. "This season is going to be a nice season for everybody. We lost a lot of energy last year."
The new ballpark is also an attraction, and the team expects it to be packed for most of the season.
Going from sparse crowds to sellouts is another change for the players who came up through the Marlins system.
In New York, Reyes was used to the spotlight. The four-time All-Star feels Miami is about to emerge as a major baseball market.
"It's going to be different," the flashy shortstop said. "The team we're putting on the field. The new stadium. The fans, they are excited. Being in Miami, I think it's going to be huge for us.
"The atmosphere is going to be something else. For us, as players, we're going to be very excited and emotional, to be there on Opening Day in the new stadium. The fans are very excited about that. That's good. I come from New York. You're always on national TV and stuff like that."
Excitement can work both ways, cautions Bell, the team's new closer.
"We just need to go out there and make sure we don't use that adrenaline against us, and use it for us," Bell said. "If we can stay calm and just go out and play, we'll be fine."