RocketStu actually they don't contradict each other. #4 is referring to being consistent (being yourself be it a corporate brand, small biz brand as well as personal brand) and #9 is referring to providing the most valuable content possible for your audience. If you blast self promotion all day it is not going to connect you with your brand.
The advice is aimed at both individuals and business. I think you would even be surprised once you start blogging and writing content even as an individual the people that may want to subscribe to your blog feeds or get updates from you via email.
For businesses, the personal voices of their employees are very important. Social media is about relationships and connecting as individuals, not just as logos. Just as you commented here, it would be great to see your face so that we could start to build a relationship. It's hard to connect with only logos and default avatars.
Also, regarding the personal brand development and voices we coach executives to community managers on how to find their authentic voice. We help them align their voice to that of the organization they work for. There are many case studies of a person working for a brand demeaning the brand with their personal profile tweets or Facebook status messages. It's too much to explain here on a comment but I encourage you to visit my blog and the other posts that are published here on Social Media Today. I have written much on these topics.
Best of luck to you and hope this helps some as you find your true voice.