

To me, not very important. Quality of writing ranks higher for me.
I don’t think a different voice can fix a bad movie. That being said, I can’t think of any actors whose voices I can’t stand.
OTOH, Brotherhood of the Wolf does come to mind here. It’s a French movie; I’ve watched both with subtitles and dubbed. The voice actor for the English dub doesn’t quite fit the character.
Yeah, that’s true. Writing alone isn’t enough for a good movie – I’m really just saying that it’s the most important element for me.