This is interesting.
In requires, of course, coding. To be able to add banner images below your header, check out wp_head action. Like:
<?php
add_action('wp_head', 'add_header_banner');
function add_header_banner() {
echo '<img src="#" alt=""';
}
Of course, it will be more complicated than that... if you want admin interface etc.
?>
For the content, you need to add_filter on the_content here.
To give each category a different banner, you’ll use is_category here and probably switch statements and the like.
