I kinda had this idea for a dream/nightmare god...You could probably give that to your "Mother of Invention" goddess. The idea being that her gift of Nightmares would serve as warnings of coming war machines while her gift of Dreams inspire wonderful inventions of peace and prosperity. She can also be associated with Visions (seeing possible futures that can come about or dreams of lost technology from past civilizations). She could carry a pouch of sand in one hand and a tool of some sort in the other (not sure what would work but then that's probably forcing the idea).