I really like the sax part and the voices are a cool idea.
I would point out that in the main repeating voice line, there is a moment when the voice breaks and it's always in the same spot, basically showing the copy/paste a little and sadly making it appear less organic.
Starting around 2:30, there are multiple vocal lines in the same register, making it difficult to follow. I think it would have been better to just keep to the falsetto and one additional vocal line (maybe two, if you can separate them clearly).
Apart from that, really cool idea and a nice performance!