Whatever happened to Terry Farrell, she ditched Becker after a few seasons too and there was a replacement character. Has nothing listed after that. She probably made some bank off of Becker in syndication though.
Fuck continuity. TOS had no continuity, and it was amazing even now.
The problem is Voyager's intent was completely different. They weren't flying all over the place to check out whatever gods or computers or chicks Kirk needed to fuck with that week. Hell, even TNG was more or less the same thing with Picard lecturing instead, but they still had character development and a sane continuity. Voyager was supposed to be a single ship on a multi-decade journey back home which pretty much implies continuity.
And for the first season and a half they were trying to set up some kind of "oh hey, we're alone, and there's this crap going on we just can't warp back to starbase from" and then a few years later we're blowing up fifty Borg cubes with all our shuttles every other episode.
The worst part is how bad Voyager squandered all their unique enemy races. The Kazon and Vidiians are easily more interesting and fleshed out than the Klingons, Ferengi and Cardassians during their respective debuts and early appearances. But nobody apparently knew what to do with them or how to even place them in the Delta Quadrant and so we got a shit load of recycled or rejected TNG plots.
Consider: The entire Hirogen arc, nor the species itself, isn't that bad in terms of introducing a species, dealing with them, having the Federation affect their culture and an aftermath coda, and it has a two-parter taking place in a WWII scenario on the Holodeck for fucks sake.
Even the Kazon arc had a semblance of a good idea with bad execution. There would be these individual sects, so Voyager would deal with different maje's with different personalities/ideologies, you had whatever that whole Tom Paris is a jerk arc was supposed to be about, Seska's betrayal, the Trabe setting up Voyager and the Kazon to try and get power back, Cullulh's insane capture plan*. It was just haphazard, came across two years instead of during a sensible time frame, and poorly executed in general. (Plus the Voyager writers never explored the aspects of the Kazon they had already built and so they WERE just Klingon clones early on, the Klingons became the Klingons we know with Worf and Moore's work, the Kazon came prebuilt with the warring sects and stolen tech and nomadic stuff and all of that went almost nowhere or was ignored.)
Compare to the Breen who got like what, five or six episodes and they're basically as fleshed out as the Kazon were over two seasons. With almost no backstory before then.
*As bad as Basics is, Suder and the Doctor is awesome.