Quick question: I've read that Mosaic and Pathways were considered to be canon for Voyager when they came out. This was because they were written by Jeri Taylor and provided back story for the characters that writers of the show could use. I've also read that the details of the stores were later overwritten. How were these novels contradicted on the TV series or was it just that their details were incorporated into the TV series?
I think Mosaic is still consistent with canon, as far as I know. As for Pathways, many of its details about characters' backstories were contradicted by later seasons of the show after Taylor left -- such as B'Elanna's parents having different names, Harry knowing different people at the Academy (and in fact Pathways contradicted the previously established name of Harry's Academy roommate), etc. And the post-finale novels by Christie Golden contradicted Pathways with regard to Chakotay's backstory, the details about Harry's girlfriend Libby, etc. The one bio chapter in Pathways that I don't think has been contradicted by anything since is the Kes chapter, since she was gone from the show by the time Taylor left.
Janeway's backstory in Mosaic has also been incorporated into the Voyager Relaunch storyline. And I in particular remember Tom's backstory contradicted in later seasons
In "Coda" Janeways dead "father" referenced the crashed shuttle in an icecap, a major event in Mosaic.