iOS 8 does not allow for extraction of the "Application Network Usage and Diagnostics", "Device Diagnostics", and "Extended User and System Databases" categories as the vulnerabilities that allowed such extractions were patched in iOS 8.  However, you can still extract the "Apple Backup Service", "Extended Third Party Application Data", and "User Media Folder" from iOS 8.

Keep in mind that the majority of data parsed from any iLogical extraction still comes from the "Apple Backup Service".