If you are looking for the ability to assign cameras to a custom depth pass, that feature does already exist. If you would like to learn how to set this up take a look at our documentation.
Custom Depth Buffer
If this is not exactly what you are referring to, would you mind elaborating a bit so I can have a better understanding and enter an accurate feature request?
I took a look at what you are requesting and went ahead and entered a Feature Request with the tag UE-16477. Thank you for taking the time to enter a feature request. Just for your own information we do have a bunch of new Show Flag options within the SceneCaptureComponent that allows you to show or certain rendering features and assets themselves. You might be able to use this as a temporary solution for what you are attempting to do.