What did you think of Eva Segeenkova's debut as Masha? She does everything beautifully (what a gorgeous dancer), but I think other roles are better suited to her - with the exception of the pas de deux towards the end of The Nutcracker. The Bolshoi version is overtly religious, and this spiritual accent suits Sergeenkova, who is a soulful dancer imho
I completely agree with you that she is perfect for the Act 2 pas de deux. I thought she did beautifully there and really throughout all of Act 2. I also enjoyed her performance in Act 1, but as you said, Masha is not a role as natural for her as say more regal and elegant parts like Raymonda or Odette/Odile.
She's just never going to look as much like an excited child dancing in the party scene as dancers who are 5'2"-5'4"-ish and more sprightly, like Maymula, Kokoreva, or Shrayner.
Given all of this, I thought she did a lovely job and it was an altogether successful début.
Another thing, I was really hoping that Moksheva and/or Petrova would get a Masha début so fingers crossed for next season. I think more realistically we'll see Sultangareeva with a Masha debut next year, which should also be a strong performance given her recent Radish and Ramze performances.
