It's correct that roosters make great pets. Not only that, but if you have a dog or other animals, a rooster is likely to bond with those and be quite content without other chickens.
However, a young cockerel will need training and discipline from now until after he goes through his hormonal phase. This is crucial as a cockerel left undisciplined can turn into quite a tyrant and even become dangerous.
He may have a mellow temperament now, but it's almost guaranteed he will go through some degree of personality change around five or six months of age as the hormones begin to surge. You can get a head start on discipline by holding him frequently and demonstrating your dominance over him.
The way you show dominance is to make it known that you are the one in control. When you pick him up and he isn't in the mood to be held, you tighten your grip, confining his movements until he relaxes, then you release him only when he isn't struggling to get free.
Pick him up frequently throughout the day, from this point on, and do this conditioning exercise. By the time he reaches the hormonal stage, and he begins to challenge you, this conditioning will make it much easier to discipline him, and it won't take but a few weeks to establish what his role is, hormones and all.
Meanwhile, read up on how to discipline a rooster with hormones so you will be clear what the various symptoms of aggression are and how to deal with them.