Small announcement but there are new reports being made available in the Office 365 Admin center. Consider it a re-vamping and expansion of what you already had. There are new activity dashboards that give you a cross service visibility into how Office 365 is being used by your end users. Reports are available for the organization and can be taken down to the individual user view.
Here is the top level report.
Here is a drill down the email activity report.
Right now there are reports on active users, email activity and Office ProPlus activations. More reports are coming on SharePoint Online, OneDrive for Business Skype for Business Online, Yammer, etc.
Announcement - https://blogs.office.com/2016/03/15/new-reporting-portal-in-the-office-365-admin-center/