There are always multiple ways to achieve your aims in PW. What I tend to do for content shared across multiple pages is add a tab to the Home page in the admin using a new 'Fieldset in Tab'. Take a look in the demo admin at fieldset_meta. This way you can add all sorts of shared content and have it grouped together, images, site name, phone number, anything really.
If things still aren't apparent after looking at the demo, come back here and ask some more.