I have ecommerce sites with 500-600+ pages and i am trying to find some seo strategy that will boost the ranking of the sites internal pages. I am not going after some competitive keywords nor am I aiming for ranking on the first page. I need something that can boost a sites ranking as a whole not just specific url because the pages are ranking for long tail keywords. I was thinking to get backlinks from high PR blogs only to main domain. I think this should boost the ranking of the internal pages also but i would like to hear if someone can offer a better strategy that i could use.