As others have said, the difference between mammal inbreeding and snake inbreeding is pretty big. I had a hard time wrapping my head around it when I first started researching ball python breeding, but four years later I've gotten pretty used to the idea (and it plays a big role in a recessive project I want to do). New blood is always good, but there's no need to go to great lengths for absolute unrelated pairs throught your whole breeding plans. Though if that's the route you want to go, you can do it by all means! I'd imagine it'd get expensive fast though.