In order to prioritize e-mails in your “Actions to Complete” folder, you can add a column, insert a priority number for each e-mail, and then sort the folder by priority.
If you need to set up a meeting with others, it is beneficial if you can give them an overview of your availability. It's easily done in an e-mail message in Outlook 2013.
You can create a rule that drops a copy of a message you send into a specific folder after it has been assigned to a specific category. This can help you to remember to follow up on anything you are "Waiting for Answer" on.