our voice, which is one that it is not discretized in any way
I don't agree. Singers play discrete frequencies (notes) like any other instrument. Vibrato, Glissando and Portamento are ornamentations or effects.
Your proposal is similar to OSC
, which was for some people the MIDI killer
The fact is that MIDI is more about music than a mere protocol for machines to talk among them. It is a music codification, a music language dialect, so musical symbols (like notes) are the core of it.