Jakob Nielsen - the leading expert on Web usability - publishes a weekly article on the topic - Usability Alertbox. Through all of the many hundreds of weekly issues and the books he has published, one theme rings loud and clear:
Keep your design simple! Keep your design clean! Don't muddle what you are doing with extraneous technologies or content.
Never, ever use technology for technology's sake alone. Every time you begin to design a class or a module, start with content. Then, ask what technology will enable me to make this content as clear as possible - and deliver it as efficiently as possible - to the student.