You don't have hens and roosters, you have pullet and cockerels. There can be a world of difference in their behaviors but it sounds like yours are going very well. At least you are worried about it becoming worse, not worrying about how to make it better. That's different than a lot of these posts and a good thing.
When you remove a chicken from your flock you can change flock dynamics. Part of that depends on how high up in the pecking order the chicken being removed is. It may or may not make much difference, a lot of that depending on the personalities of the individuals. This is one of two cockerels which potentially raises the stakes a bit.
There are a lot of different things that could happen, mainly in how the cockerels interact with the pullets. With two cockerels that age one is dominant. The dominant one could be restraining the actions of the not-dominant one. Often with two cockerels they stir up competition over the pullets, maybe leading to over-mating or stressing the pullets. If you keep both the conflict between them could escalate as they mature or they may be best of buddies. Removing one could cause a good effect or a bad, you don't get guarantees when it comes to chicken behaviors.
What I'd expect to happen if you remove one is that the remaining one will settle into the role of flock master. The cockerel and the pullets may go through some adolescent growing pains as they grow to maturity, but even going through that process the flock should be more settled than with two cockerels. There may be some short-term disruptions but overall you should wind up with a happier flock. If there is much disruption laying may be temporarily affected but those effects should not last long. At 17 weeks laying may be sporadic for a while anyway.
I don't know what your goals are for having chickens or why you want to keep a rooster. We all have different goals. Without knowing your goals I think getting rid of one is probably a pretty positive step.