This great article on user interface design highlights many of the design considerations one must consider when building an optimized web site. These principles are particularly applicable to landing page design, where the page layout is critical to driving conversion rates. Here is a table summary Digital Web Magazine’s writeup of design tradeoffs one must consider.

Design Benefit Cost
Shallow information architecture Fewer clicks to find info More clutter
Deep information architecture Clean, reduced clutter More clicks to find info
Small font More information per screen More difficult to read for some users
Large font Easier to read Less information per screen
Drop-down box Selection amongst many choices using limited space Hidden choices
Radio buttons See all selections at all times Additional space required, clutter
Icons Quick recognition once learned, aesthetically pleasing Must be learned
Text links Always understood Must be read, do not stand out as actionable items as much from other text
Abbreviations Save space Must learn or recognize
Full text Easily understood Requires additional space
Keyboard shortcuts High speed of data entry Must be learned
Point and click Intuitive Additional time required for interaction due to increase motor skills required

Read article at Digital Web Magazine