I am quite new to to Legend but an old BRP player was interested in RQII but wasn't a fan of Glorantha. But Legend has started to become the basis for out fantasy gaming. One thing I noticed is that Monsters of Legend lacked any monsters that are demon related which has caused a bit of a problem since my campaign world the problem with demons are quite common. So my suggestion for a future book is Demons of Legend containing anything demon related a gamemaster can implement into his gameworld. For example demonic cults, demonic magic, demons and rules how to create demons.