Everyone knows on-page SEO is important but it is good to remember that it only makes up about “25% of what impacts your spot in SERP” (Hubspot, see link at end of post). Making full use of your content within social media is one of the many other factors. If you are a small business or individual you need to leverage your time. Consider why Rand from SEOMoz follows the 80/20 rule with on-page SEO.
Nothing in the on-page world is going to provide exceptional ranking influence, but getting perfect is often only marginally better than just nailing the title and headline. If you’re spending a ton of bandwidth on the last 80% of work (providing 20% of value), I might re-consider your to-do list.
The time getting to the remaining percent of on-site SEO perfection is often better spent within the other 75% of factors, of which there are many.