We started with Lt Brahmas, and they were handled A LOT as babies. They have never been aggressive to other chicks, even as they age (they are 8 mos now) and the rooster is the first one to greet us when we go to the coop. They are quite curious and always want to see what is going on, but again not in an aggressive manner. They are the first ones to roost in the evening. I have one pullet that wants to be alone most of the time, but is very friendly with people. They will follow us around and are very vocal, but not loud.
Next came the Bantam Cornish, and they are quite another story. They have always been skittish, no matter how much we handle them they can't seem to grasp that we aren't going to hurt them. They roos are quite aggressive with the other birds and seem to have favorite "victims". They chase after and scream at them almost relentlessly at times. Two roos will soon be going into the freezer. The pullets are skittish but aren't nearly as aggressive as the roos.
We then got Buff Brahmas, Dark Brahmas, a Cochin and 4 Dominiques (that turned out not all Dominique). The Brahmas are much the same as my first ones, very friendly and curious and not skittish at all. The Buffs seem smaller than the others but that's the biggest difference. One Buff is a roo, and he was more aggressive than the Lt. roo. He started biting at my legs and running at me when I turned my back to him. I took some tips from others here and he is no longer a problem at all. He is not aggressive to the other birds. One Dominique roo is the most "chicken" of all my chickens - he hides most of the time and almost panics if you try to move him. He is very pretty but I'm not impressed with his personality. The other roo is good with the other birds and doesn't mind people. I have one Dominique pullet that is very quiet, and that's what we named her. She is neither friendly nor skittish with people. One Dominique turned out to be a Barred Rock and he is a roo. He is beautiful and has not caused any problems at all.
I then got 2 more Dominique pullets, well they were supposed to be Dominiques - turns out they are Cuckoo Marans. They keep to themselves pretty much but get along with the other birds when they are around. Most of the flock free ranges during the day, but the Marans seem to want to hang around the coop or pen even when everyone else goes out for the day. They are not skittish with people, but are nowhere near as friendly as the Brahmas.
From my personal experience, I will never be without Brahmas of some sort. They are very good with my son, who is 6, and get along very well with whatever we have put with them. They are HUGE birds and some people are scared of them based soley on their size, and since they are friendly they tend to come right up to people which makes some nervous. We just love them, all of them, but the Brahmas are our favorites for sure.