The Young Elites
I did think she did an awesome job of subtle world-building and creatively blending cultures for a distinctive and convincing fantasy setting.
I also like the complexity of her characterization, taking on some legitimately big ideas and challenging perspectives in portraying a traumatized girl trying to overcome her circumstances. It gives a lot of context to read her notes at the end and understand that she intentionally is writing a 'villain's' story, but I didn't quite buy the whole thing...
Again, that said, I may be unfairly critical after reading the epic, artful work of SJMaas, and will try to make time for Marie Lu's older series in my tbr down the road sometime to see if I like that better...