After a quick look around the prototype (very pretty!), I'm left with the question: what use will this be for sub-communities within a project?
That is, as an editor on English Wikipedia, I don't really care about its 5 million total articles and the gazillion active editors (most of whom appear to be engaged in philosophical debates on Jimbo's user talk page), but I do care about what's going on in my little corner of it (w:WP:BARD WikiProject Shakespeare). How will Wikistats 2.0 let me answer how many active editors there are working on my WikiProject's articles; the most viewed and edited articles within its scope; the number of edits over time on those articles; etc.? On English Wikisource this might be scoped either by a WikiProject, or by a particular set of authors. In other settings the scope might be defined by a category, or a set operation (sum, intersection, exclusion, etc.) on categories.
Overview stats at the project level like those on the current dashboard prototype, or cross-project (wiki) comparison, is far too coarse a level to useful for actual editors. Stats at that level are mostly interesting to Wikimedia management and press; all actual editors will be interested in lower levels of granularity. For instance, I would be interested in stats scoped to a WikiProject on enwiki combined with stats scoped to a category on Commons. All-project stats (totals for a wiki) for Commons would be at best a curio, and of very little actual use to me.
Or if I occasionally lift my head a little, and wonder about the health of the movement, I might be wondering how many people are editing actual content pages (an enwiki article) vs. navelgazing in Wikipedia:-space (judging by my Watchlist, enwiki editors spend most of their time on WikiDrama in Wikipedia:-namespace pages, but it'd be nice to have real metrics for this). Or what's the distribution of edits between Talk: and mainspace for a given article?
Anyways, my point is that the current direction appears to be aiming for too coarse a level of granularity to be useful to actual editors, and if this is so you might want to reassess it.
Cheers,