Altering whole environment of an existing adventure from land to sea

[Arkhios]

Yarr, me hearties! Let's par...loo? par..lah? ... PARLEY!

With the release of the latest Unearthed Arcana article (about Ships and Sea (https://media.wizards.com/2018/dnd/downloads/UA_ShipsSea.pdf)), I had this crazy idea (no doubt because I've been watching the amazing HBO series: Black Sails (again), and playing Assassin's Creed: Odyssey - a LOT - lately).

What if you were to change the entire environment of an existing adventure from land to sea, with the key locations being on islands or on ships, while the traveling in-between would happen aboard a ship or a boat? I'd imagine that the spooky and misty atmosphere of Ravenloft / Shadowfell would add good flavor on seafaring.

Let's assume you were to do it, how would you approach this (admittedly ambitious and/or megalomaniac) endeavor?

I'm honestly quite interested about this idea and any help and suggestions would be very welcome.

Thanks in advance!

[JellyPooga]

1) Take an existing dungeon
2) Rooms are islands, everything else is water.
3) Multiply the size of everything by an appropriate factor.
4) Scale up encounters.
5) Divide bigger encounters into multiple smaller ones.
(Yeah...I know this is getting a bit weird, but bear with me)
6) Fudge everything to account for appropriate adventure design and the time scales of seafaring.
7) Probably scrap some stuff because it just doesn't work at sea.
8) Fudge some more.
9) Scrap a few encounters and shove a couple more in (why not?)
10) Change a few names.
11) Run it, safe in the knowledge that no-one will recognise the original adventure, largely because it bears nothing but the slightest resemblance (e.g. "it has some goblins in it" being about the last remaining vestige of the original).

[Arkhios]

1) Take an existing dungeon
2) Rooms are islands, everything else is water.
3) Multiply the size of everything by an appropriate factor.
4) Scale up encounters.
5) Divide bigger encounters into multiple smaller ones.
(Yeah...I know this is getting a bit weird, but bear with me)
6) Fudge everything to account for appropriate adventure design and the time scales of seafaring.
7) Probably scrap some stuff because it just doesn't work at sea.
8) Fudge some more.
9) Scrap a few encounters and shove a couple more in (why not?)
10) Change a few names.
11) Run it, safe in the knowledge that no-one will recognise the original adventure, largely because it bears nothing but the slightest resemblance (e.g. "it has some goblins in it" being about the last remaining vestige of the original).

Thanks. That's all pretty sound advice (regardless of the amount of fudge)

Do you foresee any issues that would make this alteration difficult or outright impossible with Curse of Strahd?
For example, does seawater count as 'running water' (such as in regards to hindering vampires?) if I'm reading this right, vampires could fly over any bodies of water without any issues; they'd encounter problems only when in touch with running water.

[JellyPooga]

Thanks. That's all pretty sound advice (regardless of the amount of fudge)

Do you foresee any issues that would make this alteration difficult or outright impossible with Curse of Strahd?
For example, does seawater count as 'running water' (such as in regards to hindering vampires?) if I'm reading this right, vampires could fly over any bodies of water without any issues; they'd encounter problems only when in touch with running water.

With particular reference to CoS and vampires, I'll first admit that I'm not familiar with the adventure at all (though I do have experience with Ravenloft as a setting).

With that prefaced, CoS isn't (to my understanding) so much of a dungeon as it features locales. Making each locale an independent island in a chain ruled from Castle Ravenloft is the way I'd go, with some islands closer together than others; some smaller ones connected by ferry or even ford and the larger ones requiring larger seafaring vessels. Which fits into which category will be up to your judgement, I suppose.

For vampires, I'd be very tempted to forbid long-distance flight over open bodies of water; forcing them, rather, to take ship in a weakened state, much like the classic Dracula or vampire tales from which Ravenloft draws much inspiration. Granting the PCs the ability or forcing them to waylay and kill vampires as they travel, with the sea preventing the vampire from returning to their lair, as opposed to them seeking out their strongholds would be an interesting twist.

This would change the dynamic of the setting fairly drastically; forcing Strahd to rely more heavily on his subordinates and lieutenants to rule, especially on the more outlying isles. That said, I would not weaken his magical powers over the breadth of the islands; allowing him to exert his influence even if he cannot physically travel there.