Role based menu redirect
The final solution was much easier than i could possibly hope for.

I ended defining my own hooks and allow the sub-modules to implements the changes using said hook,s after checking the role of the user.
Using the example above, it became:

function sub_asl_info_alter( $page, $id)
{
  if( has_role('sub'))
    $page-&gt;content .= sub_asl_dip_info( $id);
 }