It takes some resources (I'm not at this point in my game yet) but this looks like a great 'grinder' for drifters to use as a model: https://www.youtube.com/watch?v=qn37vEkby9Y&list=PLfPHRe7NN33dPBoOnVyVr9O_Cl0CIEzWU&index=3
Basically, dig deep down, dig out a spawning platform around a central station with a moat around it, use water in the moat to push drifters into the center, use ladder mechanics such that when you kill them the corpses are pushed up to easy harvesting range away from their live friends, stock with food weapons and storage, shut out the lights on the spawning platform and go to town. From the video, it appears depth in the world impacts spawn rate and types too.