Never mind…I think I figured it out. I had failed to select Default Template under Page Attributes when using the Page Settings options. That seems to have solved the extra space directly under the header (interestingly, I didn’t need to uncheck “Header Bottom Margin”).
I did notice that there is a small shift in header text location between the Home page and another page, even though both have the same settings for No Sidebar for Page Layout. If I can’t figure that out, I’ll post a different thread. 🙂