Well, to be fair: there is a lore justification to Herne.
One of the things that I find interesting is this "literal thinking" about the lore that many seem to buy into. To me, Tolkien's writing process actually produces a ton of ambiguities and different ways for different readers to interpret the text. Now, hold my Death Star. I'm not going to say: "therefore, there's no such thing as lore, there are no rules" - as plainly, there are. We cannot quite conjure Star Destroyers attacking dragons or the Enterprise going after the Witch-King. But, that said: I don't view the lore as "hard-line, literal" as many seem to think it is. That's simply my view though
When Tolkien was drafting LOTR, including the Bree chapter where we learn about the refugees of war coming up from the south, it was not clear to him yet - as the writer - that "The Silmarillion" was in the same world as "The Hobbit." Gondor did not yet exist. Rohan did not yet exist.
But Tolkien never edited those refugees from the south out of the text. Tharbad was a flood zone and a mess to cross - and we know this from Boromir. Therefore, it is entirely clear to me, in my interpretation, that some folk at least lived somewhere in Minhiriath - though it was mostly a deserted land.
Apply Tolkien's map-scale to the lands surrounding Herne. All of a sudden, the game's smaller scale notwithstanding, it takes weeks to travel to Bree along the Greenway from the south - and months to travel out from there to the coast, virtually every other direction. Therefore, to my mind, Herne's existence preserves the lore ---almost--- perfectly.
Except for one detail: it would've made more sense to me if that caravan of folks in Andrath were fleeing northward to Bree rather than traveling southward looking to settle - since, after all, it's in the same time-frame as Butterbur talking about many folks coming up toward Bree.
But as to Herne itself - - - I see it. The text is ambiguous enough to suggest an extension of Bree culture southward that is increasingly under threat to the south, resulting in a general migration northward - Saruman's spies among them.
Similarly, with places like Umbar, Harad, Khand, etc., you could have smaller enclaves of hidden rebellion - like the Boar Clan and Avanc-luth in Dunland - who oppose Sauron, perhaps related to the failure of the Blue Wizards and so forth, and certainly lore-justified by Sam's observations during the Haradrim foray in Ithilien. They would've fought a losing battle and perhaps been forced underground - but I'd still see it as plausible and a potential way to introduce some new player-hubs in those zones.
For Nurn, King Elessar could simply send-in some Gondorian (*and perhaps some Dunedain) reinforcements to help protect the liberated Nurnhoth as they settle their new land - an extension of the Conquest of Gorgoroth if you will - and provide town services just like that camp right where Ithilien dips into Imlad Morgul.
We also need to remember something else. Sometimes, we'll automatically re-interpret a region as mostly desolate because Tolkien didn't provide as many details for it - such as the missing lands between the inland Sea of Rhun and the Great River - when, actually, there's a far more simpler and logical explanation: Tolkien was, first and foremost, writing a story. The world-building serves the story - not the other way around. You'll notice that most of the lands between the Grey Havens and Mordor are filled-in precisely because our protagonists, Frodo and Sam, and their companions traveled in them over the course of their narratives. We know more about north-central Eriador because Frodo journeys out to Rivendell. We know more about the path to Moria and Lothlorien because the Fellowship took that path. We know more of Rohan and Gondor and the lands surrounding Mordor and northwestern Mordor for those same reasons.
Why do we know less of Rhun and other places? Well, because Tolkien was a husband, a father, and then, a Professor - and finally, a writer. He had tons of papers to grade, tons of lectures to deliver, and when he found time for his writing, he was mainly focused on the stories he wanted to tell at those moments in his life. There are only 24 hours in a day for everyone; Tolkien's no exception. For another simple reason: Frodo never went there.
So, is it plausible for LOTRO to envision these places as not entirely "the blank spaces" of the map? YES. Of course, in the end- that's because my interpretation of LOTR tends to look for "the spaces within the spaces"- the realms of possibility and the sense of hidden depths and unsolved mysteries that really make LOTR work as an imagined body of myth.
The game will have a de facto distinct vision to itself as LOTRO both due to its medium as a game and also because, as a game, it really needs to provide "solutions" to those mysteries. LOTRO's Moria is far less mysterious than Tolkien's because we can explore every depth of it- and that's a natural consequence of the medium and also what makes LOTRO really fun to play! In short: "The road goes ever on and on" - and I look forward to discovering what's behind the next bend! Thanks, Scenario!
I can see it going either way. It seems to me they needed it in the middle for their storytelling to work - and to make a certain number of riders more of an active threat to it on their way to a certain destination

I'm just glad it's south of Caranost so it's not directly wedged so close to Tyrn Gorthad as the Bree-land Homesteads are now due to the nature of LOTRO's scale, which I get couldn't be helped hehehe
Cheers!
