My question is, how old is your son? If he is under 6 years old, I would be very wary. Small children can take an attack in the face, and children are usually the first victim of a rooster attack.
I personally think roosters take a bit more experience than hens do. Roosters have ruined the whole chicken experience for a lot of people. As they can become either chicken aggressive as in the roosters fighting, or human aggressive as in attacking people. It can seem to happen in an instant, because inexperienced people often do not recognize the indicators of aggression, or they blame themselves for the first attack. People often underestimate the violence of a rooster attack, if they have never seen one.
I really do not think you do have a compatible flock. You have a lot of different sizes of birds in the set up, two strange roosters decrease the odds. It might work, to be honest, the strangest things sometimes do work. But if it starts not working, you really need to make some animal husbandry type decisions to create a peaceful flock. If it does not work, the only thing you can really do is remove some of the birds from the flock.
I always have a mixed flock of different breeds, I like to tell chickens apart easily, I like an egg basket of different colors. However, I always have same size birds.
Mrs K