Assuming Sabina and Mr. & Mrs. Antrobus will be offered to stars. You need someone sexy and funny for Sabina. Wondering whether Scarlett Johansson might be interested? Annaleigh Ashford is not quite a star yet but she's a fine comedienne with a well of feeling and the kind of quirky figure that the role can use.
It'd be fun to get Richard Jenkins and Jayne Houdyshell to be the Antrobuses fresh from their film pairing in The Humans. But I'm thinking one (or both) of the Antrobuses might be non-white. (Having a White, Black, Asian and Latinx family might drive home the mythic nature of the play...)