I thought Dukat was at his best manipulating the Kai into helping him release the Pah-wraith. I loved the scenes where he feigned respect for her.
Me too. I also consider "Covenant" to be a highlight of Marc Alaimo's acting. Having seen footage of real cult leaders, to me it is very clear he did his homework on that one. It came off very creepy and convincing.
Even a slightly lesser actor could not have pulled off those post-"Waltz" scripts, but given the calibre of the actor, no, I don't regret the fact that Dukat survived "Waltz."