When viewing HMTL emails, most of the time they are not rendered properly -- see below:
This occurs whether the message is being viewed in the preview pane as shown above or whether it is being viewed in its own window.
Using Office 365 2016 64-bit on Windows 10. Screen resolution is 1920 x 1080.
This is the second major issue I have come across with Outlook. If they can't be fixed, I'll be migrating back to Office 2013 until 2016 is actually ready to be released.