Apart from those on-page techniques, off-page has always been links, links, links, links and links. Contextual links work best, but you will need to have a link source that has 'link juice' - not those spammy links that no longer pass any link juice, but real 'link juice' from legit sites, and a large quantity of those would be the mover/shaker of the SERP ranking.
Other than those contextual links, authority is yet another big factor - authority that is built based on links, that is. You can try pass authority links, or simply authority from another site to yours through various techniques like 301, etc. There isn't really a good measure in terms of site authority (previously it's PR, not it's gone), but the site's TF can be a good measure, or very similar measure in terms of a site's PR quality.