@ ZachyWachy - I would not recommend your plan. If you place the younger rooster into the flock with the established rooster, he is going to fight that youngster. If you have a LOT of room, it might work, but I don't think it will.
Do not give roosters special attention, so that they lose their fear of you. Chickens equate fear with respect. Chickens respect higher order birds, by giving them space, and moving away from them. That is what you want your rooster to do. Chickens that are pets, and sit on your lap, are not afraid of you, in chicken society, you are lower than they are, as they sexually mature, they will want to dominate you often by attacking you. Roosters are not like puppies that if treated nicely, will be nice to the hand that feeds them. This board is full of roosters turning into nightmares.
I do like the idea of a cockerel growing up in an established flock. Older and larger hens will teach him some manners. Often times, roosters grown up just with flock mates, get bigger than the other pullets, and become bullies as there is no one to put them in their place, such as an older hen.
For your stated needs of a rooster, I would cull the BA, and add the new rooster and cross your fingers, roosters are a crapshoot, some turn out, some do not.
Good luck,
MRS K