Having balanced traffic sources is like having a diversified stock portfolio. It doesn’t mean you can’t make a load of cash off a single stock but your chances of losing a lot are very high too. What percentage of your traffic is from referring sites (Facebook, Twitter, local-news.com, etc), paid advertising, direct traffic, email newsletters, search engines? Balance is something I love. Mostly because the alternative, imbalance, says it all.
I found Chris S. Penn’s excellent article on this topic at http://www.christopherspenn.com/2011/01/how-balanced-is-your-google-analytics-pie/