David, I will start out by saying that I am not a fan of computer generated voices. However your expertise is this area has made my head turn. You started out with super backing tracks, added Avanna the Vocaloid and if it wasn't for those computer artifacts between some of the words I would have thought this was an organic being singing! Super job on that!
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Never blame someone else for the road you are on.
That's your own asphalt!

64 bit Win 10 Pro, the latest BiaB and RB, Roland Octa-Capture audio interface, a ton of software and some hardware