Here's my general philosophy on the matter
- If the object (page type) will never be a page, you will NEVER go to it, then use a content only. Good example is a Banner object, you will never navigate to the banner itself, it's only for display on the home page.
- IF the object (page type) even has a remote possibility that you may want to go to it as a page, then keep it a normal page type. You can always use a normal page type as content only and just never go to it or use the Page tab, but you cannot go from a Content only to a page.
But in general, you have the right idea. Usually i create sub-folders under the home page to store Home-page Specific content objects, such as banners.