It probably depends on how many of those modules have been ported to drupal 6 already and how much work the custom module would need. Here, coder module and deadwood may be big helps:<br><br><a href="http://drupal.org/project/coder">http://drupal.org/project/coder</a><br>
<a href="http://drupal.org/project/deadwood">http://drupal.org/project/deadwood</a><br>