Paragraph styles for masters
You should be able to create a blank text box on a master and assign it a paragraph style. Then when you edit a document page based on that master, the text should be formatted according to the paragraph style. It does this already, for the creation of the page. But if you change the paragraph style of the master, there is apparently NO WAY for the new paragraph style to get applied to the document pages based on that master. Which is a huge oversight.