Remathilis
Legend
Now we're drifting from "the problem with Ravenloft is you can't win" to "the problem with Ravenloft is it's an artificial world." Different argument, but I'll still take it on.IMHO, Ravenloft's artificiality is one of its strengths and adds to its uniqueness as a game world, and it's usability by DMs.
I had two points. Hopelessness/DP and Artificiality.
Just because there's a new darklord in the domain doens't mean they are instantly in charge. Mordent, Lamordia, and Nova Vaasa, for example, all have political leaders that are not the darklord. In all three cases, the darklord lurks at the fringes of power, and in the case of the first two, the political leaders are even relatively benevolent. There's nothing stopping the PCs from crafting such a society in Strahd-less Barovia. Heck, if they can defeat Strahd, they can probably do so even without killing him, just deposing him. There ARE (relatively) safe havens in Ravenloft, Mordentshire being the foremost.
Mordentshire is my favorite domain for that reason. While a few "Evil Political Lord" domains are fun, I much prefer the domains where the monster is subtle or not in power to the ones where the Darklord rule it with full power. Though the latter has its merits for storytelling too.
The one time we ran a long-term RL game, we spent a large amount of the time in Mordent as home base.
In any case, unless the DM goes with the "Barovia and everything in it dissolves" possibility, killing Strahd is always a change for the better. No matter how many darklords may take his place, no matter if Strahd Rises from the Grave, there's one less bloodsucker for a while, and THAT'S A VICTORY.
A concrete, canon example: The people of Gundarak may not appreciate being second-class citizens in Barovia, but they are far better off than when Duke Gundar was alive. (er... undead... er... the first time around... let's just say "when Duke Gundar was darklord of Gundarak".) At least they don't have to worry about their daughters being seized by their ruler. (Unless she's the latest Tatyana reincarnation, I guess, but for the most part, no.). They are utterly unaware of the metaphysical underpinings that changed in their land. Just that one tyrant was slain, and a neighboring, less brutal one took his land. The ones on the Invidia side of the border were even better off, at least until Malocchio took over. But that's situational. If someone killed Von Kharkov, for example, and his domain was absorbed by Mordent, the Valachani would be way better off. And it can happen. Gundarak is the proof.
Still, Gundarak is proof of going from bad to worse. Sure, the heroes slew Gundarak and did something good (One less bloodsucker) but in the end they did something far worse (making it part of Barovia).
1) The realms don't shift on a daily basis. There was one major reshuffling during the Grand Conjunction, a single catclysmic event that hasn't been repeated. Cataclysms are supposed to change the world in fantasy settings. Just ask the people of Krynn, or Atlantis, or Dominaria, or Alderaan. Other than that one time, there have been the addition of new lands, including new seas, but except in the infancy of the demiplane, these have occurred simply by the Mists rolling back and revealing new land, whose inhabitants claim it was "always there."
Sure, the stability of the core is there (Even Azalin's ascension only splintered Darkon, not removed it) but supposedly any evil person COULD (and evil PCs often do) create there own domain. Oh, and the idea of Mists so thick they magically hid an ocean is still hard to swallow.
2) Nitpick: Drakov can't close his borders. But if another DL were to do so, disrupting trade, how is that different than a dragon preying on trade routes or magic ritual gone awry making a road impassible? These things happen rarely, but this is a fantasy world.
Bad choice then. (My RL is a bit rusty). I typically disliked border-crossing because some of them are very restrictive (Strahd's choking fog) and the primary use of Border Crossing is to railroad PCs so that they cannot escape. Sure, isolation is important to Gothic, but a lot of old RL modules used them as a kludge to "finish the module or else".
3) The really weird stuff like the moons has been smoothed over in recent editions of the setting. Nova Vaasa's five moons were debunked in Gazetteer V, and Sithicus, which used to have only Nuitari, the black moon only evil people can see, gained a normal moon as well as of Spectre of the Black Rose.
Good. Its a start.

5) Much work has been done in the 3e line to bind the world together as a cohesive whole. Just because the domains started separately doesn't mean they have to remain that way. The Ezran religion has spread across the Core, diplomacy between the domains has become important.
That's what I'm going on about. I'd like to see more common binding. More inter-domain religions, for example. Something to make it feel like if you walked the core, you'd get some sense this world has a common bond.
The climate issue is, admittedly, a little weird, but much like the Misty Borders themselves, and the "new lands" being revealed, the people of Ravenloft have no reason to think this is unusual. This is the only world they know; the science of even the most advanced domains doesn't go much further than Earth's 1800's. If it's the way it's always been, it would seem perfectly normal. The "ends of the earth" is a real tangible place in Ravenloft and the demiplane is a world that's just a little closer in time to its creation "myth" than most. And if you're a Barovian farmer for whom a long trip is to the marketplace in town, who cares? PCs are a different breed, of course, and in the course of their adventures may naturally start to figure out something weird is going on. But does that make it less worthwhile to save the day?
Sure, you average potato-farmer doesn't know or care much about his village, but that's not true across the board. You can't tell me the more enlightened domains like Lamordia doesn't have a bit more scientific curiosity?
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As you said, we'll never agree on exact details. Despite my arguments, I DO like Ravenloft, but I have a hard time using it for long term because of my points.