My viewpoint on raising cockerels. It's served me well for ~50; I have only had two human aggressive birds and one of those was when I decided to handle the cockerel and treat them 'nice'. The other was an interesting case I will outline later.
Starting from day one, I treat all the chicks the same, male or female. They get cuddles, they learn humans are kinda nice, and they get to live in the house for bit. I think this helps ward off later fear based aggression that may arise from completely leaving them alone as littles.
Once the young birds have hit a few weeks of age, they will be distant, rather grumpy due to pinfeathers, and in general go through a skittish stage of a few weeks to months. Some hens won't completely settle until lay. I don't force handing then, I let them do their own thing mostly. The cockerels should be able to be identified around this time. All I do is I don't re-tame them. I do re-tame the hens.
With every cockerel that has reached that stage, I start slowly refusing to handle them even if they ask for it. Cockerels are so friendly as juveniles that it's hard not to, but you have to be tough even if he's asking
nicely to get picked up. At the same time switch your body language towards him, which I hope was still confident before. Do not move out of his way, make him move out of yours. Keep your shoulders square, feet square, and move through him. Don't chase him, he's done nothing wrong, just demand respect by your stance. Don't directly challenge him; often that would constitute of staring eye contact and a slightly sideways square posture. You don't have to make these changes suddenly, in fact, I suspect gradually is better so as not to confuse the poor hormonal thing. I have only switched suddenly once, when I realised that if I didn't do something I'd have an aggressive cockerel within the week. It did work, by the way. In general, have about a bubble of about a metre radius around you and keep him out. If he walks in there to a short lunge at him, kick if needed. NO, I am not advocating throwing a rooster halfway across the yard because he walked too close to you, I mean a light shove to move him away. Drop the aggressive behaviour immediately after he jumps and runs away. If you watch the average LF cocks interacting, the dominant male keeps the lesser out of his space by short rushes. Chickens understand this sort of interaction and will quickly learn to stay out of your space.
So, that is about what I do in terms of preventative behaviour. Once a cock gets to about 2 years of age (when he is truly mature IMHO) he's likely safe to tame if you still trust him then. I have a 3 year old cock that is now allowed to come up to me when I am sitting down and poke around by my feet. I pet him or mess with his wattles sometimes too, because he doesn't mind it and he's too cute to ignore. Why do I let only him do this? Because I trust him. He is the nicest testosterone filled animal I have met. I think he is truly safe in people now, and he was raised according to the above points. He has shown a slight sign of intended aggression (dropped shoulder, cocked head) once in his life, when he was little. I corrected him immediately and he's been an angel since.
Now, what if you've been doing all this and you still see one drop a shoulder to you and cock his head, or watch you from a distance like he's plotting? These are some of the earliest signs of aggression and the sooner dealt with the better. Do the same with those as you would with trespassing on your space... short, aggressive rushes. Again, note SHORT. Constant harrying just changes the aggression to fear based as I also found out the wrong way. This can be used to rehab some roosters that have attacked humans, but generally not if they're a bad case.
Now, what about those special exceptions, those roosters that are just the sweetest little cheese puffs and the roosters that are made of smouldering evil and make you taste fear in your throat when you do chores? Those exceptions are why you have to apply common sense and have to change your methods some times. Case one: an OEGB cockerel that was as wussy as jello and refused to stop being friendly. Even if I shoved him away he'd just look up at me with big doe eyes and wonder what he did wrong to make his mommy mad. He really seemed to be different. He was quiet, meek, and good with the hens even when he was well past the stage to have started hen-chasing. So, I let him be friendly, and I'm glad I did! He was the sweetest thing, and would come and interrupt picnics and beg for some food. He particularly liked cotton candy, the spoiled booger. He would come oversee all projects, whether it was changing the tyres or fixing the lawnmower or having a meet and greet for the foster dogs. He was a character, and kids loved him.
After a while he did grow a bit more distant but he was still quite respectful until he got killed by a dog at 10 months of age.
We all miss him and I am glad I made an exception to my 'rules' for him.
Case two: a huge, brooding Australorp that scared me. Really scared. He was raised the same way as every other cockerel, and he had two brothers that were sweet little guys. Not him. He was a late bloomer and a biter from week one. Correction didn't seem to have an impact on him. He would accept it then turn around and bite again. He would bite if you came close, not in an aggressive manner, just as a that's-what-you-get type of thing and that is why he creeped me out. Repeated attempts to get him moving out of my space did nothing. I had to shove him out of my space every time I came near---he would not move in his own. I dialed u the severity of my pushes with some success. By the time he was 6 months old he'd grudgingly slurp out of my space when I approached. He stopped biting at puberty, but that eerie foreboding look still lingered. He made no outward moves to be aggressive, but I still trusted him as far as I can throw a polar bear. Which isn't far, by the way. He aged to about nine months.... and then one day he finally attacked. I immediately sent him running about three metres and repeated that every single time I saw him. He settled back down a bit but he still felt like a bomb and a match stuck in a concrete mixer. I have kids, I can't keep this monstrous and brooding thing around to possibly severely injure them. He could easily reach their eyes with his spurs. So, after much misery and deliberation, I butchered him for the table. I hated it but I could not keep such a rooster around.
Anyway, that's a long spiel about nothing, eh? I am sure I have forgotten some points, especially since body language is mostly instinctual and hard to describe. There are probably things I do that I don't even know about.
As seems to be my custom, I'll likely find some key point I missed in an hour and have to edit it in.
Remember too that these things are generalizations, as the last two special cases show. Some have luck with other methods, but this one works for me.
In your case I think getting all hens first then getting some straight run chicks and keeping a male or two out of them seems like your best bet. It worked for me when I first started my flock, and it worked for a friend of mine that wanted a male.
Also, don't be scared off by that last story. That was one bird out of 50, and the majority are great. All my Chantecler roosters are docile, sweet, and not aggressive at all.
Words of wisdom here. HE is the ultimate authority, healer, creator of all that is good.
