What's left for the Royals to do this off-season?

The Royals had a flurry of activity in December, picking up Alex Rios, Kendry Morales, Edinson Volquez, and Kris Medlen on free agent deals, following up re-signing relievers Jason Frasor and Luke Hochevar and dealing Aaron Crow to the Marlins. They also made some minor deals, acquiring Rule 5 pick Jandel Gustave, outfielder Reymond Fuentes, and signing pitcher Yohan Pino. Does this wrap up the Royals off-season activity? Here are four moves the Royals could still make between now and Opening Day.

Upgrading Backup Catcher

There has been a lot of hollering about getting catcher Salvador Perez more rest. But resting Salvador Perez could lead to a significant drop-off in offensive performance with a backup catcher in the starting lineup. The Royals went with Erik Kratz at the end of last season, but Kratz has a career line of .219/.273/.404 in 532 career Major League plate appearances. He can provide some pop, but little else.

Francisco Pena is much younger than the 34-year old Kratz, but is much less experienced at the big league level. Pena hit 27 home runs for AAA Omaha last year, although he posted a .280 on-base percentage, and had never hit double-digits in home runs in the minor leagues before. The Royals may decide they want a better option to turn to to rest Salvador Perez, although with the designated hitter spot now filled by Kendrys Morales, its unlikely they turn to a solid bat in a trade like Dioner Navarro or John Jaso. John Baker, Geovany Soto, and Wil Nieves are some veteran free agents who remain out there, as well as former Royals catcher John Buck.

Adding a Utility Infielder

Former first-round pick Christian Colon impressed fans over the last two months of 2014, hitting .333/.375/.489, although it came in the very small sample size of 49 plate appearances. The 25-year old Colon hit an underwhelming .281/.344/.385 in the minor leagues, so there is no certainty he'll be able to handle Major League pitching for a full season. The Royals also seemed to have concerns about his defense at third base, particularly after a costly error in Colorado, enough so that they signed veteran Jayson Nix to replace Colon on the post-season roster.

Veterans like Gordon Beckham, Nick Punto and Ramon Santiago are available as free agents, as are career minor leaguers like Jonathan Herrera, Brandon Hicks, Chris Valaika, and Josh Wilson.

Adding another Outfield Bat

Jarrod Dyson will be the primary fourth outfielder, and if the Royals decide to carry 13 hitters (not a certainty at all, especially considering they have Rule 5 pick Jandel Gustave), they will have room to carry a fifth outfielder. That fifth outfielder could be an internal option like Moises Sierra, Reymond Fuentes, or Paulo Orlando, or the Royals could seek to add a veteran bat to come off the bench. Scott Hairston, Aaron Cunningham, Ryan Ludwick, or Eric Young could all be low-cost right-handed options as a bench bat.

Trading Greg Holland or Wade Davis

Jon Heyman suggests this is no longer an option, but the Royals could be sending out smoke-screens to get other teams to up their offers. The Royals have no need to move Holland or Davis. However having those two, plus a deep bullpen that includes Kelvin Herrera, Jason Frasor, Luke Hochevar, and Tim Collins, is a luxury that the Royals could afford to part with if they got a great return. The Blue Jays are reportedly looking for a closer in a trade, and the Angels, Tigers, Dodgers, and Yankees are among the teams that could potentially look for more bullpen help.

What do you think? Is the Royals 2015 roster set? Or do they still have some more work to do?