The ability to administer and get Office 365 device activation information for users through PowerShell
Expand out Get-MsolUser cmd-let or add other cmd-lets to find which devices a user has activated. In addition to this, the ability to remove such activation's would be useful as well. This could be used for troubleshooting and reporting purposes. In fact, I am surprised this isn't already apart of the MSOL cmd-lets.
This Feature is very important in OS-upgrade scenarios. When you have to switch several thousand computers due to Windos 10 migration you don't want the users to remove their old work computer by themselves from the licensed devices.