Of the players you mentioned, the only 2 I think can still be on the 40 man are Pareda (they don't have other catchers ready on the mlb roster, and he can be solid depth at St. Paul) and Ryan Kreidler. I think Kreidler sticks as well for a couple of reasons. Those reasons are mostly me reading tea leaves, but...
1) Played in Detroit's system and did make his debut in Pittsburgh this year. Shelton certainly knows him.
2) Riley Greene, Detroit left fielder, is quoted as saying that Kreidler was one of the best ss's Greene had ever played with during his baseball career. His bat has mostly stunk so far, but if he does have the ability to be a backup SS defensively, then I think he has a spot here.
Generally, I think they'd work hard to also bring Ryan Fitzgerald back as a minor league free agent.