Almost all default mail templates contain a div with some styling options:

<div style="font-family:arial; font-size:12px;"> ... </div>

This div makes it difficult to define a global theme via the header and footer elements.

Instead, the default templates should all drop the div and set the styling options via the header and footer, to allow for easy and consistent styling options.

Furthermore, many templates regarding state changes all have the same subject line “New document for your order”. This should be changed to something more meaningful.