I think there should be a new gamemode for evacuation called war. You could make it that on the fifht day of evacuation you can choose defend or war. You could also make it that if the hunters are won the most matches then it would go to the war gamemode and if the monster wins most of the games then it automatically goes to defend.
The basis of the war game mode is instead of having hunters defend a generator, just have both sides go at each other. The hunters could have a bunch of colonists or Ebonstar soldiers on their side while the onster would have two minions. I’m not totally sure what the objective would be or how to balance it, but I think this idead at least deserves a look.