I have a grey as my first bird-my husband had owned a pionus previously. We found a rehome and after much discussion with Pepper's previous owner on the phone, we decided she'd be a great fit for us. The things that attracted us to greys were:
relatively quiet: Her alert call is shrill, but it is brief and she only makes it a couple times a day. I have been in the presence of a B & G squawk and it was so loud it hurt my ears and I didn't even want to be in the same room as the bird-and that was it's normal noise. Greys talk or whistle more than calling. If they have been around other birds they can pick up that bird's noises too. Pepper can do caique and indian ringneck because they were in her previous home.
Ok around kids: The kid's handle Pepper a little bit, but overall she's my and my husband's bird and we hold her the majority of the time. However, she is fine with my busy and noisy house and she isn't aggressive (doesn't attack other people to protect me from them) If she doesn't want to interact with you she moves away from you, if you persist on bothering her you will get a nip but it's not a hard nip.
size: Ours is a Timneh, a nice medium size.
ok with multiple people: we needed a parrot to be ok with multiple people handling it. She was a family bird and has been fine with both me and my husband holding her and training her. I am her preferred and she wants cuddles and scritches from me, not from hubby.
A lot of it depends on bird personality, however, not all greys have those personality factors, but Timneh greys are very likely to have them! Congo greys generally are a bit more reserved and a bit more likely to have phobic issues if they haven't had a healthy home. But the best thing to do is be able to meet your bird ahead of time.
Whatever bird you get, be prepared that your bird may pick one of you as a favorite. As long as both work with the bird, it's likely both can have a relationship, but occasionally a bird decides the spouse is the rival. It can even pick the one who doesn't do all the cage cleaning and feeding duties as the favorite.
If you are looking into greys I'd recommend the African Grey Parrot Handbook. It really explains how they think and how to deal with setting up a healthy home and behaviors really well.