probable main alternian cadaver religions:
corpse agnosticism / apathy: most common. “i dont think the ghost cares what happens to its corpse”. corpses are left outside to be eaten or stolen or whatever according to the traditional alternian method
decompositionism: still common, but a minority belief. “i believe ghosts prefer to have their corpses return to the soil / Alternia”. might have some complications throughout the galaxy: maybe orthodox decompositionists ONLY want their body to be buried on alternia, whereas “reform” decompositionists will have their body buried on any planet?
cremationism: uncommon; practiced mostly by members of the christian sufferer cult and their descendants. “i believe the ghost cannot properly manifest until the body is destroyed.” might also have a reincarnation aspect to it; since followers of the signless believe he will be reborn one day, maybe the ghost cannot return into a new body until the old body is gone?