Nothing is right or wrong when it comes to VLE design and layout. But there are a number of good practice guidelines, which should help you to produce a professional look and feel that represents the corporate identity of your organization.
The key to theme development is consistency. In order to guarantee a good learning experience, it is important that the look and feel is coherent throughout the site. Links should all look identical, blocks should be arranged consistently, and so on.
While it is tempting to be very creative with styles in Moodle themes and the arrangement of blocks, bear in mind that good design principles still apply!
Make sure you test your styles in multiple browsers on different operating systems. Unfortunately, Moodle themes are notorious for displaying correctly in one browser, but not in another. The introduction of the Internet Explorer specific style sheets has improved matters, but there is...