I'm glad you asked this. And I say this even though I can't answer it, which is unusual for me - I'm a narcissist and it really bugs me when I can't use someone else's question to show off my own smug self.
But I am still a narcissist, so I'm gonna write like a page of explanation for why I can't answer this first and only then speculate on what the answer might be; feel free to skip to the last heading.
Big city, small town
See, the truth is right now we don't even know if this stuff will work on Stack Overflow! And that's the whole point of doing it: for years, we kinda hamstrung our ability to fix problems on Stack Overflow by trying really hard to make every change work across the entire network, from Stack Overflow with thousands of posts a day all the way down to Sustainable Living which gets about one question every couple days...
That was a nice idea in theory. But it really wasn't fair to anyone; there are lots of tools that are complete overkill on smaller sites, and behaviors that don't even make sense to folks who aren't used to dealing with insane numbers of questions. Trying to even discuss these problems on MSE was getting to be a headache; some discussions involved more culture shock than anything constructive, as folks from tiny sites tried to extrapolate their small personal disagreements to SO's scale and SO regulars tried to apply the policies that were necessary there to folks who didn't so much need a rule as they needed to go somewhere else and just talk to each other.
So the first step toward fixing some of the pervasive quality issues on Stack Overflow was simply giving Stack Overflow a place to talk to itself, about itself.
A little bit of introspection goes a long way sometimes... The first two hugely-popular threads on the new MSO were focused on negativity and quality. Not new topics by any means, but indicative of a huge amount of pent-up frustration on both fronts. And most telling, folks saw these problems as representing conflicting goals, intractable by nature because trying to solve one would inevitably make the other worse.
A few people got really bummed about these discussions, but I think they're great. Finally, we had reason to stop blaming a few malcontents and start fixing underlying issues. Instead of shooting in the dark and hoping for the best, we had brightly-lit targets to aim at...
Two really hard problems
I'm gonna try & sum up the two goals of the quality project in one sentence:
Get a LOT more crap out of the way a LOT faster, while pairing up folks who CAN and WISH TO learn with those who CAN and WISH TO teach.
And here's the punchline: we're trying to accomplish both goals without pitting them against each other. Massively de-emphasize questions from folks who haven't yet learned how to ask a coherent programming question, but don't immediately nuke them - instead, provide the asker with gentle, general-purpose advice and offer anyone willing the opportunity to step in and give them some more specific guidance.
Sound impossible? Unlikely? Well... It might be. But we're trying anyway, dammit, because it's important!
And what you're seeing so far - the new review queues, that crazy flowchart - those are just the tip of the iceberg. We're building infernal machines deep underground for classifying content and mixing metaphors. They're big and scary and we probably wouldn't be getting away with it if we hadn't thought to paint "ice cream for children" in big colorful letters on the sides of the housings ahead of time...
...and we won't know if any of it really works until it all comes together. We're testing bits and pieces, a little bit at a time, and seeing what happens, what assumptions are valid and which ones aren't. It's nerve-wracking and tedious and we're using people as guinea pigs and...
...and so, you want to be a guinea pig?
This is the bit where I try to answer your question without actually answering it.
The Help and Improvement queue could actually stand alone. That'd probably be the first thing we'd consider turning on anywhere else, just to see what folks did with it. Of course, we'd have to have a different method of feeding it, but on smaller sites it'd actually be feasible to just throw in every 0-scored question from every user with less than 10 reputation and call it a day.
The content classifiers that feed Triage (and, indirectly, Help and Improvement) require training - which means we need a pretty substantial amount of known-good and known-bad posts. It'd be feasible to run on some sites, but not nearly all.
Triage itself is probably pointless on all but the very largest sites. The whole point is to chew through a huge number of questions as quickly as possible; if you're only getting a few dozen questions per day, it's unlikely that there are enough reviewers to make it work or enough questions to keep them interested in the first place. Aside: the only actions in Triage that are binding for moderators are those that are binding everywhere else: closing, deletion and spam/offensive flags - this means a single moderator can't just clear out the queue if no one else is around.
Finally, the altered Very Low Quality flag behavior only makes sense when both Triage and Help/Improvement are available. It's sorta what ties them together - without those queues and enough active reviewers to make them work, you're just forwarding all VLQ flagged questions straight to the moderators, which... is what already happens.
In short, I'm not yet sure if these queues make sense anywhere else. My gut feeling is that they'd be useful in some form on a few of the biggest sites - Super User, Ask Ubuntu, Mathematics, maybe even Server Fault if they can resist the urge to comment instead of editing... But first we have to make them work on Stack Overflow. If we can't do that... There's really not much point in trying to continue this experiment elsewhere.