I think the role of Juliette is one of those "Announce it, and there are lines out the door of the AD's."
After "Giselle" I think it has Rachel Foster's name all over it. But there may be an opportunity for a one-off for someone else, and perhaps a younger dancer, since it's an excerpt and the dancer doesn't have to learn and carry the whole ballet.
I agree, it's a role that generates incredible lobbying by dancers. And the Maillot version can accommodate a wide variety of performers, so that just increases the number of possibilities. In this specific case, though, I think that it would be smartest to cast dancers that are likely to perform it when it comes back in its full-length form -- along the lines of an audition. And with that kind of strategy, I do think that Foster would be a likely choice. She would do a good job with Maillot's extended version of classical ballet, and the dramatic content is something she is working toward.
That would make three casts, which for a duet in a mixed rep program is probably all we'll see on stage, but it's early enough in the season that they will likely teach it to at least one other cast, for the experience and the insurance. In that case I'd vote for Chapman -- she's a knockout Rosaline, but I think she might bring some interesting qualities to Juliette. But your opinion may vary.
And we haven't touched on Romeos here -- perhaps we should make a new thread for "Gaming the Casting" and open the season on speculation.