Coincidentally, Ravenloft is a setting that I wouldn't mind the occasional adventure arc in, but has little appeal to me for a full campaign. But Ravenloft is a prison. You don't just dip into it for a few sessions.
So, for me, replacing the Shadowfell with Ravenloft is perfect.
I prefer Ravenloft as a full-on campaign setting, but I don't care where it's set. Could be floating in the Etheral, the Astral or in the Shadowfell. It is self-contained, so it works wherever.The "weekend in Hell" theme for Ravenloft is a classic, but most fans of the setting tend to agree that it reaches its fullest potential as a campaign setting when it was treated as, well, a campaign setting (that is, one which had long-term campaign potential). It's why 2E's Domains of Dread and the 3.X Ravenloft Gazetteers were so popular, because they treated the Demiplane of Dread as its own place.
Making the Plane of Shadow a "place of subtle horrors" doesn't equate it to Ravenloft. For one thing, the Shadow Plane is already a place of insidiousness, and has been for virtually its entire history in D&D, being the home of shadowy and sinister creatures and civilizations.
Ravenloft, by contrast, is a realm of [gothic horror. The majority of the Core domains present a facade of normalcy behind which the true terrors lurk. The monsters there are full characters in their own right, and the terrors they inflict are often deeply personal. Your choices matter in Ravenloft, and if you make the wrong ones you can start down the slippery slope to becoming one of the monsters. And you can never just plane shift away.
Ravenloft and the Plane of Shadow may have some superficial similarities, but they are not and should not be the same place.
The "weekend in Hell" theme for Ravenloft is a classic, but most fans of the setting tend to agree that it reaches its fullest potential as a campaign setting when it was treated as, well, a campaign setting (that is, one which had long-term campaign potential). It's why 2E's Domains of Dread and the 3.X Ravenloft Gazetteers were so popular, because they treated the Demiplane of Dread as its own place.
Making the Plane of Shadow a "place of subtle horrors" doesn't equate it to Ravenloft. For one thing, the Shadow Plane is already a place of insidiousness, and has been for virtually its entire history in D&D, being the home of shadowy and sinister creatures and civilizations.
Ravenloft, by contrast, is a realm of [gothic horror. The majority of the Core domains present a facade of normalcy behind which the true terrors lurk. The monsters there are full characters in their own right, and the terrors they inflict are often deeply personal. Your choices matter in Ravenloft, and if you make the wrong ones you can start down the slippery slope to becoming one of the monsters. And you can never just plane shift away.
Ravenloft and the Plane of Shadow may have some superficial similarities, but they are not and should not be the same place.
I don't know what to say about the Inner Plane stuff, since I've never liked them, but I do like the idea of weakening the idea of planar boundaries. To be honest, one of the things I've always liked the least of D&D cosmology stuff is the very idea of planes themselves. The concept is actually a rather strange one that has more relation to modern scientific theory of alternate dimensions than to anything from the fantasy and myth that I'm familiar with. Overall, I prefer to actually take all the different places, such as the world, the afterlife, the world of the faeries, the home of the gods, and the primordial chaos, and stuff them all into the same space so you could travel between all of them without magical portals or the like.Another concept. What if all of the inner planes had a stronger connection to the material plane, wherein the Feywild and Shadowfell are what exist between the material plane and the positive and negative energy planes respectively. The concept could be expanded so that the four elemental planes also created these border-planes. Thus, there would be the true Elemental Plane of Fire, which you can't really visit, but then the Fire Realm, which is a mimic of the material plane that is heavily fire themed.
Some speculate of a Positive Plane floating beyond the Great Wheel.
Perhaps this "Positive Plane" is really the Far Realm--which would explain all of those radiant powers that Star-Pact Warlocks get.