I've also thought sometimes, I know some games where the protagonist has some of these 'monsters' as a partner, helping with the task. Perhaps a mission can be developed around it.
Garrett helping a zombie or skeleton free his soul with the help of these? Something like this
Spiders aren't always hostile either, for example in Winter Harvest, the spider in the neighbor's attic wasn't aggressive at all, or the Fire element released in The Black Mage, the ghost in Mother Rose also isn't agressive, even helps against the guard. The friendly ghosts in The House of locked Secrets, etc.. This can perhaps be extended in a direct collaboration in some future mission.