For more organizable and not confusing interface, a feature like this would be appreciated by stream operator assistant. I am not the assistant, but hell I created a lot of complex OBS scenes that could confuse my assistant. It's for the good!
I agree with matt_mexico, guide layer would also be good. I really appreciate with the devs for the recent update. Funny enough that I uses their DVD Screensaver in case of layer not picked up by OBS. I used OBS to record automatically my lecture class.