Christine's hair
As we know, Victorian ladies prefered elaborate hairdos with a lot of fake hair braided/looped into their down.
Carlotta's hair looks like typical XIX century hairdos.
Iconically loose hair was for virgins and brides, but also for prostitutes and freer women.
That last option suitable to West End wigs. Just look at these pictures:
Victorian ladies:
West End wigs:
It's plausible a young singer would wear hair like that.
On this photo, Robyn and Leila have a classic wavy hair. Of course, in XIX century there were fashionable a long hair and combing their in fancy hairstyles.
Another things are in US. Rustic wigs remind hairstyles of opera singers like Adelina Patti. Just look at this:
Similar hairs like these, had Samantha Hill and many more US Christines. There are characteristic curls from curling-pin. Victorian ladies hadn't curling-pin of course, so they curled hair on a poker or different hot metal.
Do you remember Mary Philbin? She was the first Christine. I think that Maria Bjornson drew lots inspiration from the first movie about Phantom, including one of Maria's iconic looks. When we look at Maria's hair, we remember Sarah Brightman's curly hair or Kristen Dale, Patti Cohenour etc.
