Story wise it wouldnt make much sense. He already has a voice inside him telling him stuff, if you finisehd the game (i dont know if this happens on good path im playing evil) when he goes to sleep a being tells him to keep consuming and to keep gaining power. The icon for this being is a scarred purple eye, which is MC's eye. The being thats probably communicating with us is our creator, so either the 3rd or the 4th. So another voice would complicate things. Perhaps at 3rd evolution we can get closer to our creators? That way he can speak to his monster more freaquently.