Re: Emily Blunt = Scarlet Witch?
It is a possibility.
I enjoyed her performances in Looper and The Wolfman.
It depends on how the character is written and designed (and I hope to God they do not use the *****-ass trenchcoat design from the Marvel Now redesign.)
Justice League (TBD)
Batman: Ben Affleck. Superman: Henry Cavill. Wonder Woman: Gal Gadot. Green Lantern: Tom Anderson.Darkseid: Michael Cera.
Aquaman: Alexander Skarsgard. Martian Manhunter: Liam Neeson. The Flash: Neil Patrick Harris.