I need to change all the text in my drawing to be standardized, what's the easiest way to to do this?

The easiest way is to update all of the text in a file, to the standard font, is to use the PostalCAD Update Text command.  In the Cleanup menu, pick the Update Text listing or use the UT keyboard shortcut.  All text in the drawing will be changed to Century Gothic, with the original size and justification you had before.