Being specific, once Carlson is up, the outfield depth in the pool for this season is Williams and Dean. That is it. The only other OF in Springfield is Fletcher, who has never played above Johnson City.
Cards667, good analysis. What you imply, but not state directly, is that the Cardinals would go with 15 pitchers and 15 position players. Before all the pitchers being delayed, they said they wanted 17 and 13. However, in the last few days, Shildt said that was no longer likely. My guess has been that they would still go with 16/14 because of the expected pressure on the pitching early.
However, if they go all the way to 15/15, your roster could be it. I do think pitcher number 16 not on your list is probably Jake Woodford, though. That would suggest Sosa is bumped, if Dean is on the team, which is my thought shared earlier.
P.S. Another spot that has come into question in recent days is Fernandez.