Balance with On-Page SEO is KEY. It's critical to balance best serving your audience with making your pages search engine friendly. The title of the page, the depth of research, keywords used and so on should all be used with your audience’s needs in mind. HTML headings, anchor text and more should provide clues for both search engines and your audience about the relevancy of your content. Your site architecture should also help search engine crawlers navigate your site and help users find what they’re looking for.
Off-page ranking factors tend to not be directly visable to users. Search engines evaluate reputation, the quality of a site’s backlinks, the user’s geographic location and many other factors to deliver the most relevant results. These factors can be more difficult to directly control on a per-page basis, but they must be taken into account when optimizing for search.