I frequently change the default settings for superscript and subscript characters. Rather than setting it up as a character style, I prefer to do it in the Advanced Type Preferences settings so it's consistent throughout an entire publication and I know nothing was missed. But it's a pain to have to tweak it as there is no preview option. I'd like to be able to preview it as I make the changes, or to access those settings from the character palette.
Far more sensible would be to make the setting a character-level attribute rather than document wide. The values one would want to use for these should, ideally, change from typeface to typeface. If the superscript/subscript/small-cap settings were moved to character formatting then a preview would be available automatically, either through a dialogue as with other formatting options or live if this were a panel*.
* It should not be a panel.
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