First of all, you sound like an SEO's web developer dream. I can't find a fault with the way you approach things on-site.
Off-site - again, you're going about it the right way. A focus on content is a great start.
The two verticals in which you've struggled in, insurance and dating, are two very competitive niches. I certainly wouldn't be discouraged by not getting great results in these markets first time, but you can maybe build upon your link-building and off-site work to see if you can do better.
How are you getting this content out there? Are you targeting relevant blogs, or using article sites? Blogs will be a lot more valuable and you can search for relevant blogs on Technorati, My Blog Guest, Guestr, PostJoint and Guestblogit. There's also a great Google spreadsheet you can use, which you can learn more about here
In very simple terms, the higher the authority of the blog linking back to you, the more 'strength' that link will give you (although do take care not to get links from spam sites). For certain niches like insurance and dating, with so many people competing and using underhanded ways at getting these authority links, you're gonna have a tough task on your hands. But you've certainly started going about it the right way.
