Sand - 3:03 am on Jan 23, 2013 (gmt 0)
And for the record, this site is in the same boat as yours. It's an informational site that has great content & editorial backlinks, but the traditional user metrics for search visits are horrible. Time on site and page views per visit are not good. Honestly, it's just the nature of my content & the queries that are sending me traffic. People are looking for very specific information that I provide. They find what they're looking for, read it, and leave.
Have you tried to adjust your bounce rate through asynchronous analytics tags? Basically, you just setup an imaginary event that fires at a defined interval.
When I implemented it, I learned that 75% of my visitors spend 2 minutes or more on the site (even though most only view one page per visit). To me, that's a valuable user metric that isn't measured out of the box, and it puts me at ease. I know people are engaging with my content, even if they only look at one page. Just something you might want to look at.