To get back on-topic a leave discussion of “business” for the other topic
It sounds like you are mainly a Designer.
With the recent impact of Google changing the rules for mobile sites in mobile SERPs and the steady trend of mobile use increasing, I can see only benefit for learning RWD.
Start a topic with a link to your site giving it the site-review tag and I’m certain it will help you a lot in this endeavor.
Then, market yourself as a Designer, no backend stuff, no database stuff, no content writing, no off-site SEO, etc.
It’s good, even somewhat necessary to know those things at least to the point of understanding them, but that doesn’t mean you have to be responsible for doing them.