I don't like Emma Frost much and the Frost/Cyclops relationship seems forced and has rarely worked for me BUT the one thing I do love about Emma is that she maybe the only one who doesn't bow down to the altar of Jean Grey. Even after her death, Emma still can't stand her and doesn't pretend to.
Plus, despite her various (retconned) amount of sexual experience with different Marvel heroes (Namor, Iron Man) she pretty much has eyes only for Scott and isn't a married woman constantly making goo-goo eyes and randomly kissing a surly short hairy guy (I never understood how Scott was called out for cheating on Jean telepathically but Jean's obvious public infatuation with Logan for years was OK).