I enjoyed the episodes encountering the Vidiians over the Kazon. My favorites of season 2 include: "Lifesigns", "Deadlock", "Resolutions", "Deathwish" and "The Thaw".
The Thaw is a real
nightmare, the only truly scary Star Trek episode. That clown was the most unpredictable villain in all of Star Trek. A 10 out of 10.