For me, it was always a two-hander between Avon and Vila. The sparks just flew whenever they were in a scene together.
Vila was the most relatable character though.
Avon and Servalan was the combo I liked seeing the most on screen. They had such great intellectual tension as they constantly tried to sniff each other out. But, as you say, Vila was definitely the most relatable.
Avon was a hell of an anti-hero and Paul Darrow nailed the role. All my friends at school wanted to be Avon. And don't get me started on Servalan...