Organisation membership with Drupal user account
One comment is that it would be more common to have Contact 1 set as the Individual (current user) and Contact 2 as the Organisation.

In terms of if an Org does not renew - if you have the Individual 'inheriting' the membership, and hence getting added to a Drupal Role via MemberSync then when the Org fails to renew then the Individual will lose any Roles other than Sync.

An alternative would be to use Drupal Rules based on Membership Status and hence Block the user if their membership Expires but that seems unnecessary imo if you give the Authenticate role no extra permissions.

The Individual needs to be given 'permission' over the Organisation via the Relationship, this will allow the Individual to edit some details via their CiviCRM Dashboard, though I would suggest you give them a Drupal Views block linked to a Webform and let them edit the Org details that way.

HTH