Great advice from others at the Grey Forums. I always love it when people say, "I want to get another parrot for the grey/parrot I have now". I have three parrots and I will honestly admit, I have them for me. Because I enjoy their company. My tag is my first parrot and she use to talk, now she only says, "I want a nut". She does not enjoy my other parrots she would be happier alone. My cag, is my talker and a big bully, he is much larger than my tag and my zon. He just pushes the other two off of where he wants to be. My zon, is a rehome he tries very hard to understand what I want and do it. I cannot touch him or he will bite BUT he goes in and out of his cage as I ask.
I do let them out of their cages together but I watch them as they do squabble. A nip or bite here and there. I live alone and am retired so I have oodles of time for my parrots. It is important that the human has time for their parrot/parrots. My parrots steal from each other cages BUT NEVER when the cage owner is inside of a cage. I would never put them inside a cage together because if they didn't kill each other I would have a very large vet bill ( have you ever take your grey to the vet, very expensive trip) and permanent damage to their bodies.
Roscoe sounds like a very happy and healthy parrot. Turn the radio on for him if you think he needs companionship while you are at work. Give him a big bell to play with, I believe he will enjoy that more than a "friend". He has been on the schedule he is on for 16 years. Why change it now, he seems very content with it.
Whatever you decide, do it for yourself not your grey, because you will then have to find time for two parrots not just one.