Suggest edits - currently, the Q2A site only allows granting users complete access to edit question/answers/comments without any limit. This is a strong privilege, but for the development of your Q&A site, you should have an easy way for all users to improve questions & answers. This is where suggest edits would come to place. Users could still suggest edits to the post, but it would be placed in the moderation/approval queue (could be the same as approving new posts or a separate one).
Reasons for flags - configure reasons and allow users to select a reason for flagging the post. The selected reasons should be displayed for the admin/moderator somehow (in the flagged posts queue and perhaps directly in the post)
Notifications to rejected/removed posts - allow maintainers of Q2A site to enable notifications when any of the users' questions are rejected/removed. This would send an e-mail to the author with the removed content. This should likely also introduce a custom reason for rejecting/removing that is also sent in a notification.