for the hell of it, an opera "dream cast"
just for fun, the parts for some of the characters might look something like
Ned Stark: lyric baritone (though a more masculine one, like, say, Robert Merrill)
Robert Merrill
Khal Drogo: basso cantante
Samuel Ramey
Olena Tyrell: contralto (Ewa Podles would make a PERFECT Olenna!)
Ewa Podles
Khaleesi: dramatic coloratura soprano
June Anderson (a voice heroic and powerful enough to command respect....but also capable of being a little bit girly

)
Cersei Lannister: dramatic mezzo
Maria Callas (yes, I said dramatic mezzo ideally, but the two are so damn similar)
Robb Stark: full lyric tenor
Nicolae Gedda
Tywin Lannister: dramatic baritone
Hans Hotter
a House of Cards opera wouldn't be too bad an idea. let's do a dream cast for that as well
Frank Underwood: basso cantante (Boris Christoff)
Claire Underwood: dramatic mezzo (Kristel Lindstat)
Zoe Barnes: lyric mezzo (Fiorenza Cossotto)
Lucas: lyric tenor (Alfredo Kraus)
Peter Russo: lyric tenor (maybe we could have a
tenor mad scene for once XD)
Christina: lyric coloratura soprano (Natalie Dessay)
Doug: lyric baritone (Simon Keenlyside)