Move helper settings to theme while still being overridable
Don't use default input class for radio and checkboxes
Use custom element for all setFlash() calls
More configurable icon codes and make it available as $_icons in views
Remove trailing space in icon template
Remove hardcoded icon codes and use $_icons instead
Use icon configurations from theme in the JS layer
Remove 'class' => false setting for checkboxes and radio buttons

Helper calls should not contain presentation layer code whenever possible.
This should be automatic and not required anymore since [2288038b].
Add configurable default image class
Removing hardcoded img-polaroid classes
Include 'hide' class in modal default element

Themes can override this by supplying its own modal element
Add page-heading and page-footer block similar to Common/admin_edit