What inspired this wish list request?
To my knowledge to change the FONT size for the legend in a graph (for example using Bivariate platform) the user changes the Heading Fonts size in the Files>Preferences>Fonts GUI. However, this also changes the font size in the data table for the column headings.
What is the improvement you would like to see?
Add an option to File > Preferences > Fonts GUI to enable user to customize the font size for a graph and this option would not change the data table column heading font size. Perhaps there is also a way to jsl script the customization of the graph legend font size, but I've not figured out a way to that so far.
Why is this idea important?
For presentations and graph readability a large legend font size of ~18 or larger is used. However, this makes data column headers large and makes the data table more difficult to work with and can make column headings become only partially veiwable in certain GUI windows, or sub windows with a GUI. User then needs to stretch the window to be able to read the full column name. Unfortunately, sometimes column names get long in attempt to fully describe the given column's content details.