Quick and dirty way: Open eq2ui_journals_quest.xml using Notepad, search for all instances of Zapf15 and replace with Zapf18. That will kick it up to the next preset font size. If that's still not big enough there's also Zapf20 and Zapf24.
If you aren't able to get anything satisfactory using that method, try the more complex but better fine-tuning way:
Add this near the top:
Code:
<TextStyle Algorithm="Simple" FontName="Verdana" Name="CustomFont" PointSize="18" UseCachedFont="true"/>
Then replace all instances of "/Fonts.FontZapf15" with "CustomFont".
Once you've done that you'll be able to change the font face and point size just by editing that line. You can also change the Algorithm from "Simple" to "Bold".