My absolute favorite scenes in LP's work for the show come from the Cassandra storyline. Some of her work there was actually fairly subtle, hinting at ways the character had changed from what we had seen in the preceding story.
I think the early weeks of 1795 would come in second. For one thing, the character is given fairly straightforward motives. She's actually given dialogue that shows that it's not just Barnabas, it's Josette's position and privileges that she covets. Those scenes make me think that the man could have been almost anybody--it was the fact that he was Josette's man that made him something she could not live without. Later, of course, they change that; but that's the original lay of the land, as I see it, and it makes sense.
In terms of LP as an actress, I love her work on PT 1970 because it's no holds barred, over the top scenery-chewing and she gives it everything she's got. My least favorite work from her would have to be Catherine in 1841 PT--that character was so one-note and full of herself. Really not very interesting to me personally.
I don't myself regard Angelique as being coldly calculating; she too often got distracted by her love of and involvement with her own emotions. In this respect, I do think Nicholas pegged her accurately when he read her beads as an "incompetent" Witch. The Dream Curse started out as a cool idea but the flaws in her technique became more and more apparent as it went on, particularly once Stokes got wise to her. The one really cold thing she did, and made an impressive if bloodcurdling job of, was her hex on Sarah and how she manoeuvred Barn into agreeing to marry her when she "cured" the little girl. Those scenes had me wondering whether Ang spent her free time capturing flies and moths so she could watch their death agonies after pulling their wings off. It was very disturbing television, particularly for the Sixties.
G.