1 - Dynasty: this was just so lush. So regal. So majestic. Particularly when they upped the ante with the trumpets from season two onward.
2 - Flamingo Road: as others have pointed out, it was unique and it really gave a feeling of the sweaty Southern swampland that the show was set in.
3 - Bare Essence: I know that this won't appear anywhere on the top 5 but I'm throwing it in because I love the drama of it. It sounds akin to the themes of those big miniseries like
Lace and
North & South.
4 - Knots Landing: my favourite is the season 5 version. Particularly that middle bit (bridge?) that kicks in around Constance McCashin's title card. I liked how they kept tweaking it over the years to keep it fresh, even if some of the later versions sounded a bit generic.
5 - Falcon Crest: like Bare Essence, the arrangement on this was such high drama.
Honourable mention should also go to
Paper Dolls for eschewing the standard orchestral dramatics that the other soaps used and went for a more pop theme that is probably the only theme that you could say sounds truly 80's today.