Funny that you said that. One of the common complaints about the Kazon and Vidiians were that we saw them too often, especially the same individuals. They are stranded and trying to get back to the Federation. It would make sense to have an alien of the week format for most of the time, if they keep traveling toward Earth at Warp 6. Voyager should be constantly entering and leaving territories...
Nothing in Voyager ever makes any sense. Like do you realize that it took Seven's parents about a year to get to a point from where it will take Voyager thirty years to come back? (In the first timeline) How is that plausible?