The biggest question that the Cardinals will have to answer over the offseason is what to do with their outfield. That will inform how they approach the first-base situation.
To that end, I'll consider step-by-step a possible solution to the outfield traffic jam that has manifested itself on the Cardinals' 25-man roster. This is, of course, merely an explanation of how I would approach this issue, based on my vague opinions about players' abilities and the attitude of the Cardinals towards them. Feel free to agree, disagree, or discuss in the comments.
Not counting Heyward, because he’s technically not on the team anymore, the Cardinals employ 7 above-average outfielders, with four of them capable of manning centerfield and thus any of the three positions: Jay, Bourjos, Pham, and Grichuk. The other three (Holliday, Moss, and Piscotty) are corner outfielders, with Holliday being established as the starting LF. Let’s therefore just ignore Holliday and LF for the present and concern ourselves with the remaining two outfield positions and 6 outfielders.
Clearly, the area of most depth is centerfield, although it wouldn’t be crazy to see any of Jay, Pham, or Grichuk man a corner outfield spot. No team should have more than 6 outfielders, including bench players, on the 25-man roster, since otherwise a normal roster would be missing either a backup infielder or a backup catcher.
Therefore we have a maximum of 5 spots to fill with 6 candidates left to fill them (again, since Holliday is already cemented in LF). Personally, I don’t much like the idea of having 6 outfielders on the 25-man roster, since that only allows for one backup infielder. Perhaps others feel otherwise. Either way, let’s assume that Matt Adams is going nowhere this offseason; he doesn’t have much trade value, he’s cheap, and there’s the slightest bit of hope that he turns into a solid, productive player. The Cardinals are going to give him another to chance to claim first base. However, as the Red Baron Aaron Schafer mentioned in his article on fixing the first base problem, it’s unlikely that Adams isn’t platooned, and the nice thing about both Piscotty and Moss is that they can play (competently or otherwise) both first base and a corner outfield spot. So let’s assign Piscotty the dual role of backup 1B and backup corner outfielder, since he’s a righty and Moss is not. That consolidates the bench somewhat, so that we can still have 6 outfielders and two backup infielders.
Now here’s the reduced situation: 4 spots (starting CF/RF, backup CF/COF) to fill with 5 candidates left (Bourjos, Jay, Pham, Grichuk, Moss). Let’s confront a few realities: there is almost no chance that Peter Bourjos will be the starting CF on this team while Mike Matheny manages it. Of the three other options to start in CF, Jon Jay is probably the worst with both the bat and the glove. Therefore we’ve narrowed things down to Pham and Grichuk. Of the two, Grichuk is younger, has the potential to develop further with more playing time, and is seemingly favored by Matheny. Therefore, let’s say Grichuk is the starting CF and Pham is the backup. This is fine, because Pham represents a great all-around threat off the bench: he can pinch-hit, he can pinch-run,and he can pinch-defend at all three outfield positions.
Now we’ve reduced the situation to the following: 2 spots (starting and backup RF) to fill with 3 candidates (Bourjos, Jay, and Moss). If these are the three options left to start RF, then I think I would start Moss and have Jay be the backup. To be honest, each of these three options either doesn’t excite me or doesn’t make sense (Bourjos in RF). But there’s a chance that Moss regains his form as the 3-win player he was from 2012 to 2014, and his defensive play in the corner outfield is solid. Any way you slice it, though, we now have Bourjos as the odd man out. So it’s very likely, in my opinion, that he gets traded at some point this offseason—and yes, I think he will be tendered a contract by the Cardinals. To not do so would be stupid.
All of the above described the situation in which the Cardinals do not next year employ a certain Jason Heyward. IF the Cardinals were to sign Mr. Heyward to a contract to play for their baseballing team for many years to come, then of course he would start in RF and Moss would back him up, with Jay becoming superfluous and therefore trade-bait.
Outfield scenario without Heyward:
Starters: Holliday, Grichuk, Moss
Backups: Piscotty (1B/COF), Pham, Jay
Outfield scenario with Heyward:
Starters: Holliday, Grichuk, Heyward
Backups: Piscotty (1B/COF), Moss (1B/COF), Pham
Traded: Bourjos, Jay
In summary, in my opinion, signing Heyward effectively adds to the Cardinals the value differential between Heyward and Jay--probably 3-4 wins--as well as whatever the Cardinals can get back in a trade for the Chief Justice. And either way, Matt Adams is the starting first baseman come Opening Day.
As I said at the beginning, this post merely reflects my thoughts and opinions about the players the Cardinals have and the situation in which the organization finds itself. If you agree, disagree, or think I overlooked or didn't properly consider a possibility, you can of course say as much in the comment section.