Excellent basic guidelines. Some of these might overlap with yours:
* Give the user content that they can see at a glance. If you can glance at your web site without seeing content, fix it.
* Use readably large fonts. Even those of us who have good eyesight usually don't want to read small text, and there are a lot of people whose ability to read small fonts has deteriorated with age. You don't really need to cram as much text as possible onto one screen.
* Column width shouldn't fill the whole screen without a very good reason.