Of course SEO is important because it provides the backbone of the website…but at the rate of Google changing its algorithm almost every year: Hummingbird, Penguin, Panda, Lion, Tigers, Bears, Sloth, T-Rex….etc., you are pretty much going to keep having to adjust your SEO methods accordingly. So it isn’t something stable that you can always rely on. One day it will rank on the first page, and two weeks later, it might sink to page 5.
On other hand, quality content, when you are giving valuable information, and a unique voice and vocab in your writing, will certainly stand and give fresh content for Google to read, and for even other bloggers want to link to. And the more high quality links you have, the higher Google will determine your page’s ranking in its search engine.
However, you have to be proactive in sharing your content. It will take forever to get results if you just write a superb blog but then just leave it there. You should considering social media and email marketing to gain followers, share links to your content, and thus increasing your web presence.
For your content, you can produce one blog post for a certain segment group, and then a different content for another group, and because each campaign is relevant to their interest, there will be more clicks. That is the magic of target marketing.
So basically, have SEO has a technical foundation for your site, but produce good content and utilize good marketing, to achieve more traffic to your site.