I draw only four superscript numbers: /onesuperior /twosuperior /threesuperior and /zero.superior.
At the moment, I am not in the situation to set all inferior numbers, but picked these first three since they are part of the minimum set on some font stores (and most often used in the text), and zero.superior because it was easier for me to use it as a reference for thickness when drawing these other three.
So I've set "sups" OT feature just for these four.
When I test it in Illustrator, I get proper forms through OT panel ("Position" field). But when I use the "Character" panel I get fake auto superscript forms. Is this behavior up to my OT feature setup or it's up to the end app and I can't do anything about it?