African Greys have a reputation for being complex birds, and rightly so. I have known four greys over the last ten years and each one had its own strong personality. Chips, my current grey is by turns loving and affectionate, sullen and stroppy, playful, lively and occasionally quiet and introspective. My previous grey, Squawky (and why not?), was far more outgoing and socialized. The others were also very different in manner and behaviour.
I guess I am saying that it is impossible to make generalizations about grey's personalities. Not only do they differ from bird to bird but they also change quite radically as they mature. A bird that may have been a handful as an adolescent can become well behaved as a mature adult, and vice-versa.
My current flock; Chips and Bubble and Squeak, seem to have arrived at a mutually acceptable modus vivendi. None of them are especially dominant (I like to think that I am at the top of the pecking order!). Bubble and Squeak get on together with only minor bickering. Chips doesn't like Bubble and won't tolerate him coming close whereas he is prepared to accept Squeak to the extent of allowing her to sit next to him on his perch. They don't display any bonding behaviour but they do seem to get along without the obvious need to savage each other.
I realize this is only of limited help but what I would say is that parrots do seem to have their own way of ordering their relationships and I don't think you can predict how they are going to get on.