In our design system we use design tokens for line height.
Example:
We see these as part of a “line height toolbox” which depending on context you could override the typographys default lineheight token with any of the four. The same way text alignment is always accessible regardless if youre working with a text style or not.
Making this perhaps optional if you have multiple variables/tokens within a segment would be just great.
We do the same with letterspacing and fontweight.
Up until now we have been using the Figma Tokens plugin which has allowed this. As for now with variables, it is no longer possible which means that we would either have to create a huge set of text styles, or a very annoying solution with modes.
Great to see the typography part released with variables though i am slightly disappointed that the relative values are not supported (ex. lineheight as countless others have already pointed out.