I can see it.
Saoirse Ronan is talented and has carved out a niche playing tough but vulnerable kids, and she has proven action capabilities (see also: Hanna). A superhero role seems like the next natural step, right? But Marvel is going beyond just putting a name on a top ten list—they’re prototyping the Scarlet Witch, a new character that will be in Avengers 2, based on Ronan.
This is the first time I’ve heard of such a specific character/actor matchup; even Robert Downey, Jr., still their best casting job, was a happy accident. But the thinking behind the Scarlet Witch is super specific, and tailored just for Ronan, whom, ideally, they’ll bag for the part. They’re certainly very interested.