Zarad x Widow, love the idea of her thriving in the Corval court with him. My other personal favourite is Woodly, especially if you befriend/politically marry Lisle as well. I doubt Lisle would take too much issue with an affair so long as it's discrete enough the court doesn't detect it (and if you're romancing Woodly, you're capable of that), Penelope is a sweetheart, you get to become a Queen, and you're in the same country and circles so it wouldn't be too hard to meet one another. Third place is Gisette.
(If you can't tell, I like high manipulation build delegates.)