If your neighborhood will allow you to have a rooster, go for it. I had 3-4 roosters at one time and that gets a bit problematic since they can fight over the hens .
The rooster will be the lookout for the hens when they are free ranging. He will also likely be the first to get taken by a predator, since he will try and protect the hens.
Some roosters can get mean and aggressive. I prevented this by socializing them at night, bringing them in to sit with me in the evening. Even so you might find that a rooster will sneak attack you outside. just don't let them think they are the boss. If one attacks me, I round him up under my arm and then parade him in front of his hens, so he knows i'm the boss.
Breeding can be fun, especially in a mixed bunch. when your hens are laying, you will probably be able to figure out which egg color belongs to which hen. Assume ALL the eggs are fertile. You can see that when you eat them. I found about 90% to be fertile.
The easiest way to raise your own chicks is to have a hen go broody, meaning she sits on the nest 24/7, only coming out to poop and eat a quick bite. You can then put a collection of eggs under her and she will sit on them until they hatch. It's best to collect the eggs you want, keeping them on the counter at room temp without any jerky agitation, until you have selected which will go under mommy. I keep my broody hens busy with fake eggs (golf balls).
Usually mommy can take care of the chicks by herself, but a couple time when they start hatching, i've had to help a chick out of it's shell, before it dies trying and of cold/dehydration. They survive then just fine, so you don't have to let nature takes its path.
good luck
