As for the races... Iserbyt really stepped up. It's remarkable really. He said he peaked early in the season, because he knew Mathieu and Wout wouldn't be there, so there will definitely be a decline of form the coming months. But still i didn't expect him to be, well, dominant as he has been. Of all the young Belgians, he was surely the one with the highest expectations, but (also given his miniature frame, probably expected him to be more of a van der Haar 2.0) it was never clear to me how he would transition in the pro peloton among physically powerful riders. It was clear in the U23 that he was a more talented crosser than the nearly 2 years older Nieuwenhuis (who i thought would move away from CX) who was one of his main rivals in the U23, but it was also clear on the other hand, that his other rival in the U23, the nearly 2 years younger Tom Pidcock, was more talented still.
I actually thought, after last years U23 WC, that Pidcock would have leapfrogged him by now, but that hasn't happened yet. It's quite possible though that Pidcock did not peak early in the season, coming from his crash in Tour de l'Avenir in August and that the tables might still be turned in the next few months. It will also be interesting to see how substantial Iserbyt's decline will be. I obviously do not expect him to rival van der Poel, but on the other hand it is remarkable that he's toying with guys like Aerts (who usually also tries to start the season well prepared) who was van der Poel's "closest rival" last year for the most part.
I'm kind of expecting Pidcock to also step up in a few weeks and really be a contender for top spot (behind Mathieu, when he's back). It seems guys like Sweeck, van der Haar and some others, can't really be taken as competitors any more. Their progress just halted 2 years ago. They should be gunning for wins in the absence of Mathieu and Wout, but in reality, they're already being overtaken by the younger guys like Pidcock and Iserbyt. I'm expecting Mathieu to take control with relative ease when he gets back, Aerts will improve steadily and will be battling Iserbyt, Pidcock, Hermans and Vantourenhout for second spot in the next months. Behind them, van Kessel, van der Haar, Sweeck, Merlier, Aernouts, Nieuwenhuis... will be filling the rest of the top 10 spots, with van der Haar, van Kessel and Sweeck occasionally competing for a podium spot or even a victory on a good day (in the absence of better riders) and with the form of Iserbyt and Hermans likely regressing slightly throughout the season (but maybe soon enough to be able to peak again towards January/February).