When you say "% of content/URLs viewed for a site" do you mean something like.. your site has 100 pages, but only 80 of those pages were actually viewed, so you want to end up with something like 80% of pages viewed?
This can't be done.. Only pages that actually have views will be included in your analytics (you cannot know how many pages are in your inventory from Adobe alone)... IF you need something like this, you will need to pull all the pages viewed from Adobe, and stitch this with your site database and compare which pages have and haven't been viewed, so that you can calculate this properly.
Even the logic that you listed above
Not Viewed -VISIT container with Page AND Page Views is less than or equal to 1
Doesn't make a lot of sense.. pages with 1 Page View have actually been viewed... (pages with 0 page views won't be available in your data)