This is funny, I've had the opposite experience w/my BA girls. They are the most standoffish of all my birds.
My BA roo, Mighty, was a different story though. Just like you, from the start he was so friendly and would jump on my hand or arm when I reached into the brooder. I just loved him. He stayed that friendly too, every time I would go outside he would come up and let me pet him, and even rub up against my leg.
However, he did change when the hormones really kicked in. Although he stayed fairly friendly to me, we ended up putting him in the fridge this week. I would have kept him, he was a great protector of his flock and he was Beautiful! But, he became so aggressive towards my 3yo son that he was afraid to even go outside.
I was really impressed with the amount of meat on him, he dressed out very nicely.