Is the splash at the left your surprise cockerel?
I personally like having roosters, but I grew up with them.
Most people don't need roosters. They're really only necessary if you want fertilized eggs for hatching.
Roosters aren't guaranteed to protect the flock, either. And they really can do nothing against most predators. They can give a warning call to the flock, BUT so can hens and pullets.
It's really up to you to make sure they're safe from predators. Which can be very difficult depending on what you're dealing with.