I would like to be able to modify the display of any field formatter. To to this I think the best approach is to add settings to all field display formats. Alternatively, I could create my own field formatter that applies to all field types and then show the default display formats within my own display settings.
For example say I want to have a field display settings checkbox that enables a div around the display of any field.
hook_preprocess_field()to make your changes?