It would be cool if the features for numerals accepted more (user-editable?) suffixes, in the past I used .onum and changing them to .osf is annoying, and to me the suffix still seems to be legitimate for that feature. Same applies to other numeral features of course.
But .onum is not sufficient. It doesn’t say if it tabular or not. So you need one.onum_pnum. Then I like one.osf much better.
It’s true, if there are tabular oldstyle figures, it gets complicated. That’s why a user-editable list of suffixes would be cool. Like recipes it would speed up the (re)generation greatly, make the recipe once instead of renaming glyphs in every font.
You can
a) Write a script that does the renaming
b) Set up a custom GlyphData with the old names in altNames. Then you just need to do a “Update Glyphs Info”
c) Use Search and Replace in Font View.