Coming from a CMS background I'm used to template layouts that allow widgets or content blocks to be placed anywhere on the page. So as well as sidebar widget placements, we see the main body content area as widgetable also.
A simple arrangements is to have the center content area divided into LEFT and RIGHT TOP halves and L & R BOTTOM halves with the full width CONTENT block in the middle.
Each area is available as a drag-n-drop region for widgets. These can be stacked, swapped and ordered to provide any layout.