What would be more practical would be total genocide. It is still possible for those women that you do save to be rebellious.
Not really.
Young women who are not in some relationship can (and likely will) still form one. That means they will become wives of the clan and produce kids of the clan.
Remember, not only did Men consider women differently back then, women considered women differently back then.
We need to remember that society back then was a complex as it is today. These were not "simple" people. Males within the clan were still an advantage. They were workers, farmers, warriors. The sources for such men were women, so the more women available to the clan the better. The result was almost a herding instinct. Kill off the threatening stock but keep the breeding stock.
Aslan is not a
Tame Lion