This is something I wish we had the option to activate in Cinema 4D. When I'm dealing with lots of instance objects I like to know which object is being instanced at a glance.
To me this is specially useful when i'm working on a scene that has for example a car that is still a work in progress. This allows me to leave the original geometry in the center of the scene and instance it so I can manipulate the instance. Then working on the car in a different scene and then replacing is super easy because I just need to replace what's being instanced and not copy/paste any keyframes or values.
So this is a tool I'm currently working on, right now it's simply a C4D scene with the instance + Xpresso that I drag into my working scenes and use/duplicate as needed, working towards making it into a script soon so we have a nice icon and simple one click solution.
Hope this helps!