It would be nice if one could set minimum-size (width/height) property for all widgets from a gtk theme.

Use cases: 

   * Making an accessibility theme with large widgets

   * Making a widget theme for a mobile device or kiosk setup with 
     touchscreen user interface. One wants each clickable element 
     to be at least certain size so it is usable with a finger press.

Currently those things can be achieved by combining font size with various paddings and margin properties, but not all widgets have text in them (sliders for example) - and in general it is painful to maintain such a dependency chain. Also some widgets like progressbar can be used with or without text label, basically creating two different sized variants of the same widgets, which is inconsistent and also hard to cope with especially with bitmap-based theming.

Minimum-size property would make it easier to create consistent sizes for widgets.