Others will likely disagree, but I'm a big fan of the idea that to rank for a term, you need to have the content on the site. Generally, write a page for the search phrase you're trying to rank on.
Your approach conversely, seems to be getting keyword rich anchor text pointing at your site. Not what I would do.
It seems you can't publish large amounts of content on your site. So what about starting a discrete blog on a seperate domain. Put your keywords in some sort of priority order and start publishing articles for those keywords.
For link development, there's lots of low hanging fruit for a baseline plus there's additional places you can get blog-only backlinks (i.e. botw has a blog only directory if I recall).