I can work efficiently, quickly, and well written.
My idea is
A world is invaded by an advanced civilization. The predominant species is wiped out to near extinction. However, the inhabitants of this world learn from their enemy, and create a hybrid between their species, and the invading species. The story begins with an existential dilemma in this being. Will deal with existential problems, descriptions of this world, from its aesthetics to its nature, and about other secondary characters, from both sides. Villains, it is planned, are a major turning point, and identity for the reader. Meanwhile, the hybrid is seen more as an entity that visualizes the disparity and the possibility that both species reach a peaceful solution to the conflict, so that neither is extinct.