How did Brit handle "Andor: Paradigm", which features a tiny cameo by Nog, but every other character is non-canonical?
And that shows how strong TrekLit is these days... That never occurred to me at the time I read it, and didn't realize until you mentioned it right now. The new characters that have been added to the various series feel just as part of the crews as those that originated on the show.
This holds true to the additions to Voyager as well. Kirsten Beyer has hit a homerun with Voyager so far and I can't wait to read what she has for us next year.
I respectfully disagree. It just shows how plugged into TrekLit you are. If a new reader picked up the DS9 novel or the VOY one, they would most likely be disappointed to find that none of the characters they see on screen are there. I'd think that PB would be interested in expanding their readership rather than narrowing it by getting so far afield from the onscreen canon. That is, if their goal is to keep selling more books.
All of them are there. It's been pointed out before that differences in crew in the novel lines are all due to events that happened in "on screen canon", with the exception of Janeway & Tuvok, so there's no reason for those people to be disappointed at not seeing them in the novels, even if they didn't appear at all (which is not the case). It has nothing to do with PBs decisions. In fact they have ALL appeared at one point or another in the novels, in post-finale stories (except Kes, I believe.)
To use JD's list from upthread:
Voyager
Screen: Chakotay, Seven, Tom, B'Elanna, Harry, Miral, Reg, The Doctor, Vorik, Barclay
Missing: Janeway (dead), Neelix (stayed in the DQ), Kes ("character assassinated/annihilated"

), Tuvok (on Titan)
DS9:
Screen: Kira, Dax, Bashir, Nog, Jake, Quark, Kasidy, Sisko
Missing: O'Brien (teaching on Earth), Odo (joined Great Link), Rom (became Grand Nagus), Worf (serving on the Enterprise)
TNG:
Screen: Picard, Worf, Crusher, La Forge
Missing: Riker, Troi (on Titan), Data (dead)
PB just took what was given to them by "on screen canon" and made the best of it. Exceedingly well, in fact.
EDIT: Actually, I'd go so far as to say that changes to the crew whereby a transfer/promotion is made resulting in that character appearing in another series of books may even encourage readers to check out the other lines and stick with them.