How to enforce edit suggestions of a post to require approval from the author of the post?
Try User Points


  This module provides an API for users to gain or lose points for
  performing certain actions on your site.
  
  In conjunction with other modules, such as the Userpoints Nodes and
  Comments users can accumulate points for actions such as posting
  nodes, commenting or moderation duties.
  
  Use one of the many contributed modules to extend the functionality of
  the module to include point accumulation on page views or votes,
  upgrade roles based on point balance, or purchase goods from your
  store.


And if you need to do states of content, try Workflow


  This module allows you to create arbitrary Workflows, and assign them
  to Entities.
  
  Workflows are made up of workflow states. Transitions between states
  can be allowed per role. For example, a workflow with the states
  Draft, Review, and Published could be assigned to the Story node type.
  Only users with role 'chief editor' can set Stories to the published
  state. You can set up the Workflow to alter states from form, page,
  comment and a special workflow tab.
  
  Transitions between workflow states can have actions assigned to them.
  In our example, we could assign an action so that when the story moves
  from the Draft state to the Review state an email is sent out. Another
  action could be assigned to the transition from Review to Published so
  that the node's status is set to Published (and becomes visible on
  your website).