--Don't build for Google. Don't build it around phrases that make big money in Adsense. Build it around an evergreen topic that's not oversaturated that people are interested in and want to tell their friends about.
--Offer better deals if you're ecommerce, better info if you're informational, more honesty if you do opinions or reviews.
--Skip the cult of personality. Are your sites about delivering something to users, or about making you famous?
--Provide share buttons. I know this benefits you, too, but for visitors who actually LIKE to share stuff in social media, not seeing those buttons can be a turnoff. It's not like they take up that much room or slow the page loads much.
--Provide multiple ways for people to keep up with new additions to your site, even if you can't monetize them. RSS, feed emails, newsletter emails, a Facebook page/Twitter feed/whatever that features new pages as they get published.
--Make feedback easy, and solicit it. This not only helps you tailor the site to visitors, but makes them feel important to you.
And the final rule is one I have trouble with: ignore Google's rules and do what works for visitors. For example, if you believe your visitors would enjoy a guest post or a giveaway or a page with 350 links to widget resources, do it even if you're afraid Google will think it's some kind of linking scheme. From the beginning I've told myself to build on the assumption that someday Google will flat out ban all my sites - I don't believe that at all, but it's a good mindset. Ultimately building for Google just isn't sustainable.