I really enjoyed Untethered Sky. Obviously there's tighter writing constraints that come with writing a novella, but I thought Fonda Lee did a great job of building connection to the characters and setting up the plot for her sort of signature twists/stakes. Worldbuilding wise, this story felt more like it existed in a bubble, but I'd rather have connection with the characters than worldbuilding in a novella. Overall I really enjoyed it and would recommend you check it out even if you've not read Lee before!