I'm a sucker for books like this and they could not make the encyclopedias comprehensive enough for me.
I'd have gladly paid double had they added more. I have the ShB artbook too (well, my fiancé does) and while a lot of love clearly went into making these books, I was hoping for something that really went all out and it feels like they really had to be reeled back in so they could be sold at a more reasonable price.
However, the way they screwed over the staff that actually made the books... I'm not surprised we'll probably never get a 3rd encyclopedia and shame on SQEX.