AFAIAC, if Carey is not writing a TOS book she's totally slagging on the characters.
I'm not quite sure what you mean by "slagging", but Ghost Ship
was not disrepsectful to TNG in any way. Sure, there were some characterization issues since it was written so early in the show's life (particularly between Riker and Data, also Picard was rather more irritable than usual, at least so I thought), but overall it did treat the characters positively. Overall, I thought it was pretty good for a very early TNG book.