Here's a thought I had this morning that I've since run quite a ways with:
What if the Burgomaster of Vallaki is right?
What if the only way to permanent end Strahd's curse (or maybe not even Strahd's curse, but the curse on all of Barovia) is to restore hope to the people of his realm?
There's been some discussion (in this thread and others) about how the relic & ally hunt portion of the adventurers serves as a pretty weak framing device for the need to steer PCs towards "here are the things you for you to do to get more powerful (both directly in acquisition of goods and allies and indirectly in sweet sweet XP/milestones and levels) until you're actually ready for Strahd". Several people have mentioned bringing back the fanes from the 3.5 version of the adventurer, which if made explicit is a better method of steering the PCs away from Ravenloft initially but is still primarily replacing "find three whatzits" with "find
and destory three humdingers", which isn't really all that much more stronger thematically.
CoD makes it clear that killing Strahd is a temporary measure, both for Strahd and for Barovia. Barovia is, seemingly freed from the Demiplane of Dread, as least temporarily, but also only somewhat partially (why then, would "soul-less" Barovians fade into nothingness if they try to leave, but "souled" Barovians seem fine?). Obviously the Dark Powers still hold some power over the realm and its people, even back on the Material Plane, but the grasp weakens measurably while restoring the life of their favorite Darklord. Once done, they can then turn their attention back to Barovia and drag the whole realm back into the Demiplane of Dread. This particular order is important especially if you intend to run CoD as Strahd pulling a
Thanatos Gambit, as it gives him a bit of a window to actually escape or at least spread his influence out to plot a future escape; after all this might not be the first time this particular cycle has played out. This in turn makes Eva's loyalties considerably more questionable, and in general allows for the campaign to carry on past the adventure itself and/or into future campaigns in other settings.
But that's a digression. The real question to ask is: "why?" Why do the Dark Powers care so much, not just on continuing the torment of Strahd, but also the denizens of Barovia? They can't just be incidental victims in all of this; otherwise why give the realm as a whole a glimmer of freedom before yanking back on the chain? That this answer (and the Dark Powers in general) are meant to be inscrutable are supposed to be a part of its charm, but as a DM running them I kind of still need to determine that information for myself. Any time I run an Eberron campaign I certainly know what caused the Mourning, or whether the gods are actually real forces or not. That I get to decide that myself (and change my mind any time I restart the setting) is part of its charm too. So my answer to this is actually pretty simple. It's a Demiplane of
Dread, right? So the Dark Powers need to feed on the dread of their demiplane's inhabitants. And in fact, they only have the power to directly manipulate or interfere with those who have fully succumbed to that Dread. Hence, why Barovians (and newcomer PCs) with souls still act as if they have some kind of agency, while those without souls do not. It's also why the PCs and en-souled Barovians can flee the realm while Strahd is dead and those without them cannot.
So I drop the whole "no souls from birth" aspect and replace with "most people have their souls mostly drained at an early age". So I make it explicit to the PCs from practically the word Go (or at the very least no later than their tarokka reading) that Strahd cannot be permanently killed because he is too firmly in the grasp of the Dark Powers, but that the realm and its people can be freed if only hope can be restored to the land. I envision this having a number of pretty significant impacts.
1. This suddenly makes pretty much every side-quest in the realm much more significant and meaningful beyond "here is where you can find an important whatzit" and "here is where you can get sweet sweet XP/milestones to make Castle Ravenloft/Strahd less scary". You can replace (or add to) your whatzit-hunting with the more nebulous and much more daunting goal of "bringing hope to the land and its people". Now all the Silver Dragon stuff is pretty essential. Other major subplots to resolve include the Winery/Druids/Blights, the Werewolves, the Abbey and the Dusk Elves. Some of these might require more work than others to fit into this framework (CoD doesn't really give you a happy ending for the Dusk Elves, for instance, so at the very least you'd have to come up with a way to redeem Patrina after resurrecting, or better yet find some other way to solve their inability to procreate, such as changing "kill all the women" to a more direct curse to be lifted.)
2. If CoD
is a Thanatos Gambit on the part of Strahd then it gives the PCs agency to still screw up his plans. In this scenario, if the PCs are successful then Strahd is brought back with nothing but an empty castle overlooking an empty realm. What's more, it leaves Strahd as the Dark Powers'
only play-thing, which certainly doesn't play into his hopes of escaping.
3. Vargas Vallakovich is no longer an amusingly incompetent bureaucrat but a potentially valuable ally if he could just be convinced to... you know, stop being such an amusingly incompetent bureaucrat. This could be an incredibly fun situation to play out at the PCs try to simultaneously convince Vargas to change his methods while protecting him those that mean him. Or they may decide to replace him someone more sympathetic (certainly not the Wacthers) but who the town would also accept as their leader. Do the PCs figure out how to fill that role themselves? Vallaki pretty much becomes the central location for the stand against Strahd and the Dark Powers, in this particular scenario.
4. Speaking of, the Dark Powers are now a more menacing and directly antagonistic force in this scenario. Treat this as a pro or a con as you wish. Me, I'm pro.
5. Dealing with the Abbey also becomes more interesting, especially if you decide that the Mongrelfolk (or at least some of them) are perfectly happy as they've been made. It muddies not just the Abbot's intentions (which were always muddy) but the impact of those actions (which could potentially be more in line with the PCs want, if not in the way they'd want it).
6. The Amber Temple still needs a bit of a re-design. I'm honestly okay with the implication that the Dark Powers were once vestiges, as long as there's enough clues laying around to suggest that they are the ones that
escaped (or were at least set free). I'd even be okay with Strahd's vampiric origins taking place here. "I want the power to make someone love me for eternity". Sounds like the sort of pseudo-romantic, thickly controlling thing human-Strahd would ask for that would get him turned into a vampire. "Oh, and can you also throw in the power to turn into a wolf? Wolves are awesome." I dunno, it's definitely the aspect of this scenario I'm still working the most on. Might as well tie the cure to whatever is ailing the Dusk Elves here, along with an appropriate sacrifice. Like I said, this part's a work in progress.
7. The players get to see the actual impact of their activities as they turn a drab, lifeless world into one that seems to actually support a semblance of life. They get to see their progress in the world and the people around them, and with the frustration and desperation that Strahd begins to carry himself towards.
8. And if all this "bringing hope to a hopeless land" is a little too heroic fantasy for anyone, you can always heavily drop hints that Strahd himself can be redeemed, or at least convinced to let go of his desires and his despair and move on, which would also free him from the Dark Powers. That he of course cannot be, and that destroying him before doing so only means the Dark Powers will bring him back only more broken and bitter and determined and hellbent on spreading his darkness again, but is still necessary to at least free the rest of Barovia, can be a nice little dark cloud to hang over the otherwise admittedly happy ending. The Dark Powers still live, and as long as they do, they can drag other realms that have fallen into despair into their Demiplane. Perhaps with their very own Darklords?