Hi Barb and Leah,
This one comes with a proceed-at-your-own-risk warning, but I did just figure out a way to increase the font size on a report (in this example, the name of a task):
valueexpression=CONCAT("<big>",{name},"</big>")
valueformat=HTML
The result in my browser (Chrome) was that the Name column appeared in a font that looks about 25% larger on screen...but it is not honored when the report is exported to PDF or Excel: the <big>...</big> simply appear as text. Also, since this approach is no longer considered best practice, I'd suggest you apply it sparingly, if you do choose to use it.
Regards,
Doug