Making good designs is really less about the content, and more about user interface design principles. For example, how one would encourage or explain certain actions if there were no text. (Visual cues, icons, etc...) Or common locations for UI elements of different types.
If you wish to modernize your design skills, you'll need to think about how a user will look at the site. For example, how wide do you think a user would like to read content that is filled in your page? What kind of content do you think people would expect, and where? What would be most familiar to your grandmother?
I recommend you familiarize yourself with the concepts listed here: http://en.wikipedia.org/wiki/Principles_of_user_interface_design
This is also a good article: http://blog.teamtreehouse.com/10-user-interface-design-fundamentals
And another: http://uxdesign.smashingmagazine.com/2009/01/19/12-useful-techniques-for-good-user-interface-design-in-web-applications/
And this is a pretty nice reference if you get stuck: http://ui-patterns.com/
Design is an art, so can't really treat it like development. You will find yourself using many of the same concepts other sites do, this is because you want your design to be intuitive, and one thing that people find intuitive is familiarity.
Also looking through what you've linked I noticed this:
<!-- I use id's because it makes my naming conventions more strict and I think it makes my code cleaner -->