Art is great, Cult distribution charts and "What happens in Sacred Time" are good but sadly no relationship charts between Cults, most of the information is in other sources and the information about heroquesting and every myth, particulary "I fought we won" is almost a footnote.
My opinion of course, we need the setting going foward, we are locked in 1625 for more than two years and we really need the GM book for battles and heroquesting at the same level that the shamanic rules in the core book. I think is not too much.
And the answer "use JC material" is a poor excuse. No serius company says "hey I know my product is lacking of a component I am talking about all the time, but look!, use a third party product to compensate while I decide when I should fix it"