Schreiber has impressed me this season; good starts which is a massive help, the endurance will come and she'll hang near the front longer. I'm guessing after a hard road season, Zoe is probably targeting the later season - the Nationals, where she'll only have Anna Kay to beat - and then the U23 Worlds.
Blanka Vas is a massive talent, but I've no idea what her best discipline is - as yet, she doesn't have many major titles to her name even at U23 level, most of the others have done that. She seems to come up short. I do think she jumped up to Elites too early.
Agree, the bar is substantially higher with these new kids.
In fact lots of the other "old(er) generation" riders are also struggling e.g. Worst, Kastelijn, Cant, Lechner etc and even some of the "new" like Blanka Vas, Bakker, Van Alphen and Schreiber. I think it's a good thing that Pieterse and Van Empel have pushed the level both technically and physically. It will elevate the interest for cyclocross and in particular women's CX just like MVDP and WVA has.
I'd guess Kastelijn is now a road rider, who does a bit of CX, Cant & Lechner are at the end of their careers. Another name who gets talked up is Honsinger - but she simply isn't fast enough, and needs a heavy mudbath to get near the front, and I don't think she's brilliant on the technical side. The two youngsters are fast, and have the technicals skills; the new breed of CX racers!!