I know the question wasn't aimed at me, but on the 'character' singers thing...sometimes a song doesn't need a technically great voice to carry it off. I Was Born Under a Wandering Star and the spoken singing from the Henry Higgins part in My Fair Lady both spring to mind. Sometimes what you really need is just charisma, and being rough around the edges and untrained might even suit the part better.
I do think, though, that those sorts of songs/roles tend to go to men more than women.
With full on musicals, you almost always really do need the training and technical skill to carry it off.