Outstanding work by Jeremy Crawford et al. to create a chasse for monster design that is easy to use, as well as flavour text to inspire adventure ideas. The flavour text is so good, in fact, that it makes for excellent leisurely reading. A far cry from previous monster manuals.
Really the only (very minor) drawbacks are that I would have liked some generic descriptive text to read aloud to players as they see this monster. I understand that this edition's design philosophy is to empower the DM more, but descriptive text being present wouldn't hurt that objective at all.