I would like to see a "keep in panel" checkbox added to the menu that appears when right clicking on an application icon. This option would work best when using window buttons with no labels, only icons.

Checking the box would keep the application icon in the panel after the application quit. Clicking on the inactive icon would launch it again. Unchecking the box would remove the icon from the panel when the application was not running.

With this feature, a panel with only the window buttons plugin would make a simple, effective dock. It would show apps that are running, and have the ability to "remember" favorite apps by right clicking on them while they are running.

Using this option in the main panel (in icon mode) would be a very efficient use of space. There would be no need for separate, dedicated launchers for apps.