Also agreed. I'm an advocate of Wizards releasing supplements of at least 320 pages in length, we need more Eberron: Rising from the Last Wars, with that amount of page length all of the salient information that falls onto the DMs to evoke could be included in the actual setting book.
The Dark Lords, although having stats in that they are actually utilising MM stats, should really have been statted as unique entities with unique Dark Lord powers, and have their own lore entry. Likewise with the named NPCs mentioned in the book. Though they're all given personality traits, ideals, bonds, and flaws which'll serve as good inspiration for roleplaying personality.
The monster entries in the bestiary seem to be moving away from lore snippets, instead going for a more evocative, cohesive entry.
Hopefully we'll see a Volo's style supplement for specific groupings of monsters, a supplement dedicated to horror monsters would be awesome.