I think you did well with this song.
Thanks!
I think a part of the problem is that we are comparing with real un-modified human vocals. It will take years before we get there.
I've got to say, I've been fooled by some
Synthesizer V songs. But typically, they've not been English songs. I think the uncanny valley is the factor here - we're
very good at hearing problems with voices, and where they are "off".
It seems to me that people who have embraced
Vocaloids have also embraced the sorts of singing characteristics that make them unnatural. But why not? If you've got an electric guitar, there seems little point in using it like a nylon string guitar.