Reporting: One Graph Per Instance (Host / Datasource / Instance) option?

This feature request is very straightforward, and I cannot think of a reason it's not already an option. Reporting should feature an option for "Per Instance". This arbitrary combination is already possible for graphs in the GUI, and it's possible for reports, but only "Per host".

Example: I have multiple hard drives: C: D: and E: , I would want to combine the reads, writes, and idle time datapoints onto one graph per hard drive.

Here's the problem with the current choices:

One Graph Per Host - Puts C: D: and E: all on one graph.

One Graph Per Datasource - Puts C: for multiple servers on one graph.

The solution should just be cloning the logic for "One Graph Per datasource", and modifying it to also separate by server name.