THAT'S where the Mongrelfolk appear! That was a long time coming!
I don't think it's sales to be honest. If the upcoming AP is successful and the followed it up with a Domains of Dread book covering all of Ravenloft then it would sell extremely well. They are trying to keep all the focus on Forgotten Realms while using Ravenloft as a little side trek.
I admit that I'm out of touch. I started playing 5e after not having played DnD since 1e nor any TRPG since the early 90s. But when did it become an expectation that an adventure would have class options.
The idea that every single product must be part of a grant story is rather limiting. Sure, they don't need to do what TSR did, but they can't ignore the fact that some non adventure books can sell very well.
I had already known they were missing, but it is still sad to see a lack of Dark Power checks. Not having Dark Power checks in Ravenloft is a bit like not having psionics in Darksun.
I don't understand why there would be a bunch of character options. If the conceit is that the characters are drawn into Barovia from outside, then those options would all be non-Ravenloft stuff.
There were no Dark Powers checks in the original adventure. This adventure has almost nothing to do with Ravenloft the Campaign Setting.
So from the looks of it.
No new mechanics to use as a DM unless those marks of power are that. Even then that seems really small for a setting with a COMPLETELY different feel than the standard.
No new player options.
No real look of Ravenloft in any real depth. Just possibly a brief intro to Strahd and Barovia.
Man. This is starting to look disappointing. I know I'm not the target audience, but still..