In reply to Chip Bennett.

Visual clues - as an example - having buttons with graphics on them for - left sidebar, right sidebar, two sidebars, three sidebars, etc. etc. Same applies for menu positions, extra header and footer blocks etc, These all work well in an options page layout, but might not do so well in a customiser style side bar.

Also, the idea is to show not just what the button does but what the effect looks like BEFORE it is applied to the page, therefore the site preview is not the requirement and does not provide the solution sought. The graphic on the button does it far more clearly.

Flyouts? Pfftt ... several people I know would immediately refuse the solution if they had to make use of such frippery. They want basic and solid, at-a-glance, blocks of options, not gizmos for spotty teenagers. We are of course talking about corporates here, though it also applies to sole traders and family businesses.

Unless you can offer a customiser format where the page is the options and the preview is in a sidebox, you are asking everyone to accept a massive paradigm shift in site admin, and will lose a lot of supporters and users due to it.