I will often copy a page and then move it to where I want in the menu. But, If I want a top level menu item that does not link to a page, I have to create that in the menu instead. In the page editor, we should be able to at a minimum, add a blank page that does not have a link. Or, the menu tool and page tool should be merged.
Hey Brian,
Thank you for your post.
Actually, you are referring to two very different tools. The page manager is where you set up the structure of your site, plus add meta tags and SEO data. The focus is here is rather on the structure of the page
The menu however is where you change between automatically generated or custom setup. That however is tied to the menu preset directly. The focus here is the design.
Therefore, we decided to a long time ago to not merge those too or overlap them 
Hope this clarifies the situation.