Question

it would be cool to integrate a reference tool into the master bus so when mixing, users can A/B their mix to a commercial project.

Answer 1

1. Add BUS.
2. Rename this BUS to "MASTER MIX".
3. Direct the signal (Routing) from all channels to this BUS "MASTER MIX".
4. Add to this BUS "MASTER MIX" your plug-ins for mastering and MMultiAnanlyzer (Melda Production).
5. Add BUS.
6. Rename this BUS to "Reference".
7. Add Reference Track and direct the signal (Routing) to BUS "Reference".
8. Add plug-in MMultiAnanlyzer (Melda Production) to BUS "Reference".

Now you can analyze your track and compare it with others.
You can press "M" (mute) on BUS "Reference" and then the sound will not be audible, but on the analyzer it will be seen.
Enable "Solo follows Selection". Now you have the opportunity to listen to the required track quickly. To do this you simply select BUS "MASTER MIX" or BUS "Reference".

Big picture http://imgur.com/XKYdrUY

Answer 2

Obviously those who think this is an unimportant idea must not mix intensely.