I’m loving the new messages features with inbox, sent, archive folders. Nice job.
It would be improved by displaying the profile header and horizontal navigation (activity, notifications, messages, badges etc) when viewing individual messages, just like on the message list. As it is now the messages have no context and it’s hard to find your way back to your message list.
An alternative might be to provide a link to the messages folder it is in directly under the title, e.g. inbox, like you see categories and tags for post topics.