Can I configure Send by Email to use CC instead of BCC?
You could try the hook_mail_alter() which lets you intercept emails used by drupal_mail(), but that's problematic since, as you mentioned, each email gets sent out individually. 

There's a hook_print_mail_alter() invocation before the email is sent, but this is problematic too since $params doesn't have the email recipients.

The route I would take is to alter the email form submission handler with your own custom submission based off the print module's implementation:

/**
 * Implements hook_form_alter().
 */
function MYMODULE_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  if ($form_id == 'print_mail_form') {
    $form['#submit'] = array(
      'MYMODULE_print_mail_form_submit'
    );
  }
}

/**
 * Submission Handler.
 */
function MYMODULE_print_mail_form_submit($form, &amp;$form_state) {
  //@TODO: Implement your own email code.

  //print_mail_form_submit($form, $form_state);
}