We believe you should remember that a Web site is a piece of software. Few site owners seem to understand this, and even fewer Web designers do. Web design has become the domain of the graphic designer, which is a big mistake. A Web site is a piece of software. It has to do something.
People click on links and buttons to make the site actually do something.
So the primary concern should be user-interface design. Once you have a Web site that works, you can make it look good. You shouldn't work the other way around. If it hasn't been mentioned in here, at least in passing, it's probably not worth worrying about. I highly recommend this book, and the earlier one.