i already put in a request to have an option of selecting which passes to render out.
as an extension of that, it would be fantastic to have a pass defined by the layeers or tags.
that way one could export certain objects groups as mask for easier comping.
That is an interested suggestion reminding me of Cinema4D’s compositing tag and object buffers. I don’t know if this is something possible with the Unity API at the moment, but I will certainly take a look since it can indeed be very useful 🙂