How serious of a candidate is Nico Hoerner for center field? Are Ian Happ and Albert Almora Jr. likely going to platoon center field if Hoerner doesn't work out? And does Nicholas Castellanos play a factor in any of this?
--@captaincub1012 via Twitter

If the Cubs re-sign Castellanos or add a different player for right field via trade or free agency, it would definitely impact the situation in center field. Just like when Castellanos arrived in July, that would push Jason Heyward to center field. That is one route Chicago could take. Or the Cubs could explore trading Kyle Schwarber and altering course in left.

I don't think the chances are high that Hoerner is in center field come Opening Day. If he makes the Cubs' initial 26-man roster, I'd imagine it would be as their second baseman. But the fact that the Cubs experimented some with him in center in '19 at least gives the team's front office something to have in the back of their collective mind.

So, as things currently stand, it does look like Happ and Almora would be a partnership for center. The "as things currently stand" caveat is important there, though. Almora is a trade or non-tender candidate this winter. Happ might also be a trade chip, or he could be in the mix for a more versatile role for Chicago than simply playing center.

A lot could change between now and Opening Day, but the Cubs need to solve center (87 wRC+ in '19).

Could you do a comparison of catching, defensive and framing stats for Willson Contreras vs. Victor Caratini? Based purely on an eye test for last season, my guess would be it isn't even close, with Caratini leading. Thanks, Jordan!
--@evanjjohnson11 via Twitter

Both Contreras and Caratini took steps forward last season, but the numbers definitely portray the latter as the better defender overall. That said, advanced defensive statistics have their flaws and it's worth at least noting that Contreras (811 2/3 innings) had nearly twice the innings as Caratini (426) behind the plate.

The one area in which Contreras had the clear edge over Caratini was controlling the running game. The Major League average for caught-stealing rate in 2019 was 26 percent, and Contreras checked in at 29 percent (16-for-55). Caratini threw runners out at a 17 percent (6-for-35) clip.

Blocking has been a strength of Contreras' over the the years, but Caratini had more blocking runs (0.9) than Contreras (a fraction below 0.0) last year, per Baseball Prospectus. Per BP, Caratini also finished with 3.1 fielding runs above average, compared to -7.7 for Contreras.

In terms of pitch framing, Caratini also rated better according to both BP and Fangraphs. BP had 3.4 framing runs for Caratini in '19 vs. -9.4 for Contreras. Frangraphs had 1.6 framing runs for Caratini and -8.9 for Contreras.

What is the latest on the coaching staff changes?
--Michael B., Northbrook, Ill.

The Cubs have not announced the 2020 staff under new manager David Ross, yet. Here's what we know right now.

Third-base coach Brian Butterfield and long-time strength and conditioning coach Tim Buss are both heading to join former Cubs manager Joe Maddon's staff with the Angels. Multiple reports on Wednesday indicated that long-time bullpen coach Lester Strode will also not be returning in that role '20. According to The Athletic, former Padres manager Andy Green is under consideration for the bench coach vacancy. Mark Loretta, Maddon's bench coach in '19, is also believed to be in the mix for that job.

The Cubs have not made any formal announcements about any other staffing plans, but both The Athletic and 670 The Score have reported that there will be changes to the mental skills department and training staff. This comes after the Cubs also announced some changes at the top of its player development department, which now includes a director of pitching (Craig Breslow) and director of hitting (Justin Stone).

When Cubs president of baseball operations Theo Epstein said "real change" was coming to the Cubs this offseason, he was not just talking about the Major League roster. Chicago is giving its entire operation from top to bottom a facelift.

I was surprised the Cubs didn't pick up Kendall Graveman's option. I know he missed all of last year coming back from Tommy John surgery, but $3 million didn't seem like too much given his experience and the Cubs' need for pitching depth. What gives?
--Jeremy W., Chicago
You're right, the Cubs need to add rotation depth this offseason. The team took one step in that regard on Monday by adding righty Colin Rea to the 40-man roster. Rea had a standout comeback showing for Triple-A Iowa last year following his own comeback from injury, and he has Minor League options. He joins Tyler Chatwood, Alec Mills and Adbert Alzolay on the depth chart behind Yu Darvish, Jon Lester, Kyle Hendricks and José Quintana.

The Cubs need more depth than that, though, and know that they haven't ruled out keeping Graveman as part of the mix. While Chicago declined his team option, there is still a chance that the club tries to keep him in the fold on a different type of contract. We'll see how that one plays out.

What will be more important is for the Cubs to try to add an impact starter for the big league staff this winter. No, don't count on Chicago being in the hunt for Gerrit Cole, as much as he would make sense. Instead, I'd expect the Cubs to try to find some rotation depth via the trade market.

Do you think there’s any chance the Cubs sign an infielder this winter? Specifically, any chance they would bring back Starlin Castro?
--Derrick, Alpha, Ill.
One trait of Castro's jumps out: Good contact rates (82.5 percent overall and 90.9 percent on pitches in the strike zone). His defense, however, was average at best (-2 Defensive Runs Saved and a 0.8 UZR/150 at second) and he had a .300 on-base percentage. Not sure I see him as a fit, even with the Cubs in need of figuring out second base.

There are so many unknowns surrounding how the Cubs will address needs via trade this offseason, but I'd rank adding an outfielder ahead of an infielder right now. Hoerner will be in the mix for second, and there is a long list of other internal players (David Bote, Daniel Descalso, Robel Garcia, Tony Kemp, Addison Russell and Happ) to sort through.