Not so much in Stargazer's case. The 6 books we got are basically a complete "season" with an arc that's resolved in the final volume. I think it was planned out as just those 6 books, with the option for continuing them afterward. It's just that the option wasn't exercised.
A shame as well. It's true the original 6 books does come to a conclusion in that there are no major story threads left hanging (though, of course, there was always room for more). But there are a lot of years between the last Stargazer book and you're Lost Era tie-in, "The Buried Age." At the conclusion of the last Stargazer book Captain Picard is the undeniable captain, with no more interference from the Starfleet brass. It'd be interesting to see them continue. Plus, Jack Crusher was not yet part of the crew in those earlier books and of course he had already died some time before "The Buried Age," so we never really go to see much of their friendship, outside a few mentions here and there in flashbacks of other novels.
While I'm not holding my breath, the renewed interest in Captain Picard thanks to the Picard show perhaps will reinitiate some interest in reviving the novel series. Other than the other doctor we see on Picard (which could probably be easily explained and brought into line with the existing series) there's probably not much chance of major contradictions since Stargazer is decades before Picard.
Personally, I'd nominate Christopher for that
, assuming something like that would interest him of course. He already touched on that a bit with "The Buried Age" which definitely felt like it could have been in the same 'universe' as Friedman's earlier Stargazer novels. And I always thought Christopher and Friedman had some similarities in their novels, both like world building, continuity building and character development. I could see him adding and building on the existing characters from the earlier novels and adding new characters as well (as well as giving us more details about Crusher once he joins the crew). It's one reason I always felt Christopher's "The Captain's Oath" had a similar "feel" to Friedman's "My Brother's Keeper" trilogy--even if the narratives don't fit all that well--for instance, they both depicted Kirk's earlier career with a similar philosophy, not as a maverick, but quite the reverse.

