Originally Posted by chiefchirpa
My candidate was Sienna Miller if Thor is someone older (actually she's an OK pick even now). I pick Amber Heard because her age is comparative to Chris Hemsworth's age, but Branagh most likely picked an unknown Commonwealth young actress.
You basically have to adjust the actress age toward the leading actor, not picking the actress just for the sake of her. If Sean Connery is Thor, you can have Diane Keaton as Amora. And no you better not have Megan Fox as Sif if Zac Efron is Thor.
What's wrong with having Megan Fox play Sif?