CHICAGO -- The Cubs' offseason of change began with a makeover of the player development department and continued with the hiring of David Ross as the team's new manager. More change should be expected for a team trying to get back to being a World Series contender.

Theo Epstein, the Cubs' president of baseball operations, said after the season that he believes the franchise got caught in the "winner's trap" of relying on methods that worked in the past. So, as Chicago plots its course for a return to the postseason, it will be closely examining its roster in the coming months.

"There will be some changes," Epstein said at the end of the regular season. "That's our responsibility as leadership, to take a look at everything that I personally can do better and we can do better as an organization, because we are extremely energized and optimistic about our future. It's incumbent on us to build the next Cubs championship team."

• Ross' to-do list: Choose Cubs' coaching staff

With that in mind, here are five questions facing the Cubs with the offseason in full swing:

1. How will Ross handle managing former teammates?
That will be a storyline that persists the rest of this offseason, during Spring Training and throughout the 2020 campaign. There is no getting around the fact that Ross -- a catcher for the Cubs in 2015-16 -- is friends with former teammates still on the roster. That said, there are only 10 players left from the '16 World Series team, and that number could drop further depending on how the Cubs' approach their winter maneuvering.

Ross had a veteran edge to him as a player. On the day he was hired as manager, he made it clear he would not hesitate to hold people accountable, even those he still considers close friends.

• New skipper Ross 'perfect' choice to lead Cubs

"Those guys know I’ll be the first to hold them accountable," Ross said in a statement, "the first to demand their best daily effort and the first to let them know about it if they give anything but their best. I never had a problem dishing out a lot of tough love as their teammate, and that won’t change as their manager. We'll have our fair share of fun along the way, but working hard as a team, playing fundamental team baseball and winning a lot of games will be our top priorities."

2. Will the Cubs shake up the core via trade?
The past five seasons have been built around a core offensive group featuring Javier Báez, Kris Bryant, Willson Contreras, Anthony Rizzo and Kyle Schwarber. Each of them is at a different stage of salary structure (eligible for arbitration or under contract) and the Cubs will be closely examining their potential fit for 2020 and beyond. It's possible, perhaps even likely, that Chicago will trade from this group in order to add impact players to address other needs, while also extending the contention window. It would be hard to imagine anyone on the Major League roster being off limits in trade talks under the current circumstances.

3. Which internal free agent is the biggest priority to re-sign?
That would be outfielder Nicholas Castellanos. Not only did Castellanos instantly become a fan favorite, but he energized the team and sparked the offense with incredible production in the second half. He's a unique free agent, given that he is entering his age-28 season. Agent Scott Boras will be aiming to capitalize on Castellanos' breakout season, but there is mutual interest and a definite fit. Castellanos will also be watching how the Cubs approach this offseason and factoring that into his decision. After experiencing a playoff chase with Chicago, Castellanos very much wants to keep that taste in his mouth.

• Latest Castellanos rumors

4. Who will the team be targeting to upgrade the pitching?
The rotation is not getting any younger and it's losing Cole Hamels to free agency this winter, though MLB Network insider Jon Heyman reported on Thursday that Yu Darvish will not opt out of the final four years and $81 million of his contract. Nonetheless, adding a starting pitcher is one of the team's priorities in the coming months. The Cubs already spent big to get closer Craig Kimbrel, and the team will be hoping a regular winter routine and normal Spring Training will mean better days in 2020 for the stopper. With Steve Cishek, Brandon Kintzler and Pedro Strop also among the Cubs' list of free agents, expect Chicago to be on the hunt for a setup arm to add to the group of younger impact arms that emerged this past season.

5. What positions are in most need of upgrading?
As things currently stand, that would be second base and center field. It is not a coincidence that rookie Nico Hoerner -- who filled in admirably at shortstop for the final few weeks -- got a look at both second and center in the Minors and in the Cubs' last two games. He will be in the mix for a job come Spring Training. Re-signing Castellanos would impact the outfield alignment, especially if both Jason Heyward and Schwarber are back in 2020. Without Castellanos, the Cubs will need to examine if a platoon of Ian Happ and Albert Almora Jr. is the way to go in center, or whether Happ should remain in the mix at second, where Chicago also has options in David Bote, Daniel Descalso, Robel Garcia, Tony Kemp and Addison Russell. There is a lot to sort out in that list of names.