WordPress general content best pratices

Using custom post types for this seems like a bad approach. Instead, create a simple option page in the admin using add_options_page, displayed in the menu under “Settings”, for example.

Lay out some input fields for each piece of data you want to save. You can use the options API to read and write each field: get_option and update_option. You could also use shortcodes API to pull up options right inside the post editor.