Be able to create an appointment from an email and info from the email is automatically populated in the email. It could also add the person who sent the email as a guest or guest suggestion.
Allow the use of Email signatures that can be used for standard emails to be addable to the email body when creating a calendar event. At the moment you have to type in a "Kind Regards..." manual. This looks unprofessional.
Add mailbox setting option to order the conversations/emails above the thread w/preview pane below
This is request is to be able to customize mailbox layout similar to GMail, MS Outlook, YahooMail, or other email clients to have message preview reading pane on the bottom rather than to the right of message list.