As to Rosemary's Baby - Hollywood and the TV industry are so devoid of an original idea that all they can do these days is revisit classic films and do them worse, all pandering to the "me/now" generation that doesn't have the sensibility to watch an older film without thinking it dated. The fact is, there is NOTHING dated about Rosemary's Baby - it is one of the most perfect films ever made with a cast that cannot be bettered and it is also the best adaptation of a novel ever done for the screen - it IS the novel. Including Son of Rosemary is inane for many reasons. First reason, most people HATED Son of Rosemary. While I liked it better than most (for me Ira Levin can do very little wrong), I think they're using it specifically for its trick ending, a big bad mistake. Re that trick ending, I think I was one of the few who saw it coming a third into the book, when Rosemary is watching a movie on TV. Normally it wouldn't have tipped me, except that the movie she's watching has a trick ending and I thought "why, out of all the movies he could have chosen is she watching that one". I was right.
Bottom line: You don't have any Ruth Gordons, Sidney Blackmers, John Cassavetes, Patsy Kellys, Maurice Evans anymore. And television certainly has no Roman Polanskis, William Frakers, or Richard Sylberts.