This is one of those shows where the whole thing just bleeds together and you lose track of what's what--like just about every other CWB show.
I never saw any episode more than once or (a few) twice, and it's been like five years now, so if someone was to show me an episode I don't know if I could tell what season it was from. The writing probably did suffer over the years, but the dialog manged to always stay fun, from what I remember. But the whole point of watching the show was the outstanding cast and wonderful menagerie of characters. That never really changed.