Okay so here's the thing, Kanako last season was clearly not that great because Polina Shelepen almost beat her at the JGPF, those two were pretty even. This season, Polina hasn't medaled at any big events and even has come out 0 for 3 against Risa Shoji, who is younger with no reputation and has major UR issues, in the 3 times they have competed against each other this season. So Kanako made a lot of improvements over the summer/this season, and she is doing really well in seniors and even has a chance at a world medal. That's why I was defending Polina earlier, there's no saying the same won't be true for her. If she works hard in the off season and stays injury free, there's no reason she can't be as successful in the senior ranks next season as Kanako was this season.
Also, regarding Kanako this season and Adelina and Liza this season, I'd say they are all pretty even, and if anyone is heavy edge, it's Adelina not Kanako, just look at their scores. Anyhow, Mao and Yuna weren't perfect when they made their senior debuts, but they still managed to be factors right away, so I assume the same will be true for Adelina and Liza barring injury or an extra nasty encounter with the puberty monster. I know Adelina and Liza may look like little girls, but they really don't skate like juniors.