Re: Did Voyager get better or worse when Kes was replaced with 7 of 9?
The show definitely got better (though I still enjoyed the early seasons), but whether or not it could have been achieved without Seven is unknown. TNG and DS9 also improved significantly after their first few seasons.
Kim: I'm detecting some weird technobabble.
Janeway: A possibly dangerous anomaly that we know nothing about?
Kim: Yeah. I suppose we should steer clear.
Janeway: Ha! Good one, Ensign. Take us in, Mr. Paris.