Ghost system used to have that... you cast transcendental awareness and you could see souls in form of light balls.. The system worked fine as was.. Maybe the only thing supremely polished in MO1. Should revert back to it.Using voice in ghost mode isn't OP. It's amazing. Honestly I hope it never get removed:
Seeing people is OP though. At least with no skill investment. I hope it gets removed and then added back as a subskill of spiritualism. At the point we can banish ghosts it's pretty balanced if you have to invest in being able to do it.