The ability to save an individual Stereo Aux Mix for a particular user so all the routing/sends they create for their mix is saved to a recallable library/scene similar to eq, compression, channel libraries etc.
Scenes doing this already. You can filter the recall to a specific mix only.
+1 on adding a mix library. It would be an easy and logical way to pull up a mix without having to mess with multiple scenes/scene safes. Easy to train for less experienced engineers.