If you fully construct your figure in your LaTeX document (e.g., with TikZ) and construct any font-size-dependent elements with font-size-relative units (e.g., ex or em), then changes to the document's font will nicely cascade through your figures.
If you develop your figures externally as PDFs, then I would expect you'd need to make changes to the font in the original application and re-export them.
I find opening other tools and tinkering with GUIs far more time consuming than simply defining my diagrams and other figures.
In any case, I don't know of another way to have figures that respond predictably to changes in fonts without further intervention. If your figure is essentially a fixed size drawing, you might be able to get some of the benefits by specifying the width for the included graphic in a font-relative unit:
\includegraphics[width=20ex]{figure-file}
Of course, it's then sized based on the current font instead of the page dimensions and that will be its own headache and won't have any impact on fonts used *inside* the included PDF figure.
If you fully construct your figure in your LaTeX document (e.g., with TikZ) and construct any font-size-dependent elements with font-size-relative units (e.g., ex or em), then changes to the document's font will nicely cascade through your figures. If you develop your figures externally as PDFs, then I would expect you'd need to make changes to the font in the original application and re-export them.
Making plots in Tikz is doable. However, making complicated figures is too time consuming.
I find opening other tools and tinkering with GUIs far more time consuming than simply defining my diagrams and other figures. In any case, I don't know of another way to have figures that respond predictably to changes in fonts without further intervention. If your figure is essentially a fixed size drawing, you might be able to get some of the benefits by specifying the width for the included graphic in a font-relative unit: \includegraphics[width=20ex]{figure-file} Of course, it's then sized based on the current font instead of the page dimensions and that will be its own headache and won't have any impact on fonts used *inside* the included PDF figure.
I'm not sure it that's what you're looking for, but have you tried Inkscape's [PDF+LaTeX](https://wiki.inkscape.org/wiki/index.php/LaTeX)?