I find that roosters raised with just hatch mates are often just as you describe, much more outgoing and braver than the pullets. They are just darlings, and people cannot imagine that changing. However, roosters with just hatch mates grow faster and mature faster, and they are the biggest of the flock, and often times become bullies. There is nothing else big enough to give them some chicken manners.
Roosters are not like kittens and puppies, that if you give affection, they become life long affectionate pets. Chicken society is different. Every time, any two chickens meet, one of them is submissive, and one is dominant. When you preen him, you are being submissive. When he sits on your lap, you are being submissive. He will eventually more than likely begin to tidbit you, and if you are not submissive enough, he will find that a challenge.
Most daycares are for children under 5. Most roosters will attack children first, then women and finally even men. A rooster attack has ruined the whole chicken experience for a lot of people. Small children can easily take the attack in the face.
People who are just starting out in chickens often times miss the cues that the darling is changing. This board will shortly be full of where the darling became the nightmare.
My advice is a hen only flock until your children are older than 6 years old. I recommend a hen only flock the first year, get some experience. Roosters take some experience in my opinion. Then after a year, consider getting a year old rooster, that has a proven track record.
If I had a day care, I would not risk the chance of a rooster escaping and attacking one of the children. I think you are risking quite a bit. I have a rooster, and a large set up, but when my grandchildren are here, extreme caution is practiced, and if I had them every day, I would not have roosters. And I do have experience.
Mrs K