Default Font Size in Custom Themes
Options
You should be able to set a default font in a custom theme that will minimally impact row report widgets that are set to remove format. The default for row reports without format are much to small.
In order to use my dashboards in presentations, I need to change the size of fonts in my sheets in order for row reports to be readable. This is very burdensome and it breaks the philosophical idea that summarizing and displaying data should not require you to change your data.