Let's cast the Silmarillion

[Lalaith]

I must have Joaquim Phoenix as one of the sons of Feanor, I don't care which one.

Also, I am rather taken with the earlier suggestion of Angelina Jolie as Luthien. Luthien's Mary-Sue qualities are something of a problem and Ms Jolie is edgy enough to dispel them.
Halle Berry as Yavanna? (Again, thus dispelling irritating hippy earth mother quality)
French actresses are in general a Good Thing. Good call of Emmeline Beart, Ang, but I'd prefer her as Idril....and Catherine Deneuve as Varda.