I am beyond excited to hear that another Samhain DOB is in the works!!
Some random thoughts....I like the idea of using the blood moon, but not for all 78 cards. Maybe use the blood moon for the major arcana, then choose four other moon phases for the suits (waxing and waning crescents, lunar eclipse, and regular full, silvery moon). Or maybe use the blood moon for the majors, then choose four Samhain-y symbols for the suits, like black cats, owls, ravens, and bats. (??????)
I absolutely love the idea of a borderless deck. And I prefer both the vintage paper and brown colored backgrounds because they provide that worn, aged appearance your decks are known for.
I'm excited to see what you finally decide upon!