Content approval by roles workflow
I think for your use can you should use workbench 
with workbench_moderation 


  Workbench Moderation adds arbitrary moderation states to Drupal core's "unpublished" and "published" node states, and affects the behavior of node revisions when nodes are published. Moderation states are tracked per-revision; rather than moderating nodes, Workbench Moderation moderates revisions.