I will say that Servalan in the long run was the worst. It stems from the fact that they felt a need to have a opposite villain and really Blake and co. were fighting a system, not just a villain. In the first season Servalan is a good character, rarely scene and under pressure from politicos while turning the screws on Travis. In the second season the rot starts settling in with Servalan appearing in places far too
dangerous for the head of space
command to be. I could see Servalan meeting the crew in
Orac as the mission was exceptional, but in
Weapon or Pressure Point it seemed ridiculous. She was at her best in episodes where she was not directly invovled with the crew: Trial, Voice from the Past, Star One. Afterall, she's just a cog in the Federation machine itself.
In the 3rd season, Servalan becomes president of a "runied empire", so seeing her on a star
cruiser surrounded by mutoids seems correct. Near the end of Volcano, after failing to capture the Liberator, Servalan and a mutoid conclude that without Blake, the Liberator is no threat and that it will keep. Then she forgets this and tries to capture the blasted ship in 3 more
episodes. She was starting to remind me too much of Wyile E. Coyote, Genius. I did like her setup on Terminal, but she still interacted with the crew too many times and should have died on the Liberator in her moment of triumph. The less said about the Sleer character the better, though I did like her role in Games.