Okay...we agree it shouldn't be a straight 'redo'.
DEFINITELY, they should take it s l o w l y.
I think the orig. pacing of the show (pre-1968) was one of the better parts of DS.
You had 'regular' issues/problems, plus, if you watched closely, perhaps there was something ethereal (but you weren't POSITIVE, because it wasn't in your face).
Deep, dark secrets....think Laura Murdoch, Stockbridge, Collins et al. Was it one, or many?
Also, as far as the 'regular' issues; there was possible blackmail (actually, there was definite AND ALSO possible black mail read Roger, Laura, Burke and Sam).
So, what 'extra' type stuff DIDN'T the 'spooky' side of DS deal with?
Mummies....witch stoning (don't laugh, as a youth, this scared & interested me).
How about a whole 'Gaslight' type approach...?
They did Leviathan, but, with cults you could spin it from a few different angles, without getting too preachy.
IMHO....
Patti