What do you consider the best or worst episode of Highlander. For me it would have to be Revenge of the Sword and then the Zone. Neither of these episodes were too interesting.
Some of Highlander's best episodes: The Hunters, the Kalas arc, Homeland, Brothers in Arms, Chivalry, The End of Innocence, The Valkyrie, Comes a Horseman, Revelation, Forgive Us Our Trespasses.
On the other end, the whole 'Ahriman' arc has to be the lowest point in the show's history. And 'Avatar' was the worst of the trilogy; it did very little to advance the plot, and was even more dull and pointless than 'The Zone' and 'Revenge of the Sword' put together.
I have to agree with your choices.
The zone was just a hard one to get interested in or even care about.
I didn't like "The Zone" much, but I loved MacLeod's line at the end. "The problem with thinking you're the strongest guy around, there's always someone stronger." ::comence ass-whoopin::
For me, I think the majority of Seasons III - V were excellent, with only a few blunders. Season I and II were both very uneven, with many great episodes ("Band of Brothers", "An Innocent Man") getting fumbled by horrible eps ("The Zone", "Vampire")
Best episode IMHO - the first season episode Studies in Light. I actually wept (and I'm a pretty tough cookie!). Worst - oh gosh, where do I begin? Vampire. The Zone, definitely. Revenge of the Sword.