I voted for Pilar. The comparison with Melissa simply put her at too great a disadvantage for her to win over the fans, even though she certainly had potential of her own. Given her background in finance, she could have worked for a bank on Dynasty and handled loan matters with Adam or Jeff—eventually becoming a romantic partner for one of them (in seasons 8 or 9). I also found the idea of Pilar Ortega serving as Sable’s assistant in the ninth season appealing.
Otherwise, I think that Nicole Sauguet was the most Dynasty character on Falcon Crest. I can easily imagine Alexis once seducing Nicole’s husband—destroying the marriage and driving Nicole to seek revenge. She could have appeared in Dynasty’s fifth season instead of Lady Ashley (which would have made Rock Hudson and Leslie Caron that season’s guest stars). Her primary goal would have been to destroy Alexis; she would have planned to ally herself with Blake and eventually seduce him—knowing full well that this would deeply wound Alexis. However, when Blake rejected her, she would have supported the revolutionaries in Moldavia and acted as the mastermind behind the Moldavian Massacre, aiming to eliminate Alexis and all her entire family in one fell swoop.