Editing label font: italics, etc?

[symbiologist]

Love the package - it's been a gamechanger for my work. Is there a way to set the label font to italics or bold? Looks like this can't be set in a theme as it appears that the label font is set with geom_text. I see that there is font.radar but that only allows changing the font family, not fontface.

Thank you!
David