I had some barred rocks last year and found them to be more aggressive than the others too. Even as chicks they were more "plucky". I eventually culled them.
Also, 4 roosters is likely too many with the ratio to hens you've got. For fertile eggs, 2 would be more appropriate, with less competition and fighting. However, to some degree they will establish a pecking order eventually and fight less viciously, if you are wanting to keep them all (they sure are nice to look at anyway).
Something also to help the low-on-the-totem-pole chickens would be to set out an extra feeder and waterer or two, so everybody gets fed. I also keep a few extra nest boxes for the shy hens to go retreat if they want, and also two roost poles so they have options. If you have a safe enough situation in which you can let them free range some during the day, I find that keeps mine busy and content.
You may want to cull a few (starting with a couple roosters) if you find them just driving you crazy with all the fighting. I got tired of hearing mine bang against the sides of their coop.