This S curve is generated using a smoothstep function on 0-1.
Velocity = [0, 13, 25, 38, 51, 64, 76, 89, 102, 114, 127; 0, 4, 13, 27, 45, 64, 82, 100, 114, 123, 127]

And this one I had obtained after multiple calibrations. Its slightly more extreme from the curve above. I like switching between the two at the moment depending on mood.
Velocity = [0, 1, 19, 34, 44, 56, 67, 81, 99, 118, 127; 0, 0, 10, 27, 44, 67, 89, 110, 122, 127, 127]

Hopefully it helps you all. If you guys have different curves that are working well on this one, do share!