Thats because she is an author and a book person don't you know. She can't be authentic about anything, she treats it the same way she does theatre, like dress up and make believe.
Mamma Mia could possibly one but again she needs to be funny, and also be able to act. There are some real moments of emotion in that show.
So many roles rule her out in some way. She could maybe do Addams again as Morticia, but that's more of a comic role. If
The Witches of Eastwick got a revival, she could be one of the witches, I think she'd enjoy that as they are supposed to be sexy - again though, it's a comedy. There's been talk for a while of reviving
Starlight Express in the West End, she's not athletic enough for it. She doesn't have the comedy, range, or phrasing for Mrs Lovett. The fact of struggling to sing classically without belting rules her out of a lot of older shows. Playing Audrey, or Elphaba, would require her to act and her voice is nowhere near strong enough for Elphaba. Maybe Disney or fairytale musicals - again, stunt cast Elsa for a tour/before it closes, or Beauty and the Beast if it comes back to the WE, or the baker's wife/Cinderella in
Into the Woods which is performed fairly often (though again, both these roles require comedy and emotion!) She doesn't feel she should have to work on anything and that excludes her from so much, which will only work against her as she gets older. Especially if she wants to only ever be a lead