A lot depends on the age of the father rooster. If he is over 3 years, then I would be tempted to keep one...for a while anyway. A spare rooster raised up in a multi-generational flock is a nice thing to have. This is because I would expect a rooster at that age, to be either near the end of his life, or I liked the young rooster better. Eventually, I would be planning to go back to a single rooster.
But MORE depends on your numbers and space. Roosters need more room than hens, and multiple roosters need more space than one, by quite a lot. And even then, it quite often does not work to have multiple roosters. Roosters are a crap shoot, as in sometimes they work, and sometimes they don't. Their behavior on Monday, has very little influence on their behavior on Tuesday.
I would not want to keep full time multiple roosters with less than 25 hens. My own personal preference.
Mrs K