Not only is Hans a pretty lame twist villain, King Runeard has a personal connection to the main characters in a way that none of the other villains do.

None

Hans, he's sooooo hot. And it's an amazing Disney villain. Too bad he wasn't in the sequel.

And as for Runeard, I wouldn't count him as the main villain of Frozen 2, since he had a measly minute of screentime, and he was also dead, so not an enemy Anna and Elsa need to defeat.

None. They are either badly-written or forgettable.

^W

What if Ruenard returns as a Lich as he encountered a darker power that rivals the four elemental spirits?

None of them.

RUNEARD WINS

Prince Hans is The Greatest Secondary Villain Antagonist of The Frozen Franchise