If you’re able to keep boys, then it should be fine. Your setup looks about a good size for their age at the moment, but you may have to upgrade it in the future.
In my experience, roosters need more space than hens. And pullets with a young aggressive rooster need hide outs, different levels in the run, roosts and hide feed bowls.
If they are all the same age, then you might have trouble, when the hormones start raging. Do come up with a way to pull your cockerel out of the pullet flock if he bothers them too much. Often times they get bigger than the pullets, and without older birds to thump manners into them, they can become a bully. A dog crate, can give the girls peace.
If you can remove him, permanently, it often times is a good decision. An all hen flock is a nice way to start this hobby. Roosters take experience in my opinion. They can become violent and aggressive, regardless how you raise them. Many inexperienced people vastly underestimate just how violent they can be.
If you are allowed to have him, I personally would keep him. If he becomes aggressive you can separate him then. I haven’t had an aggressive rooster yet but I have only had two roosters in my 7 years of having chickens.