Lest we forget there are the Americans and the Japanese ladies who have great jumpers and improving artistry. Liu, Tennell, Rika, Kaori, and the up and coming Koreans. Russia is not even guaranteed a medal at the next olympics.
Not that this is a topic for Alina's return, but if you put the things this way...
Alysa, Rika and Young You are the only ones that could threaten, in good consteation of stars, the current top russian ladies.
As for the othres:
Kaori? Umm, I'm sorry to talk about her this way, but your formulation doesn't give me other option than to remind that even with how many times people are sending Alina to the grave, still all her last season's results were better than Kaori's (Alina's worst score was 205, Kaori's best was 202). She has obvious consistencty problems, not to mention her problems with self-confidence, which she herself pointed out.
Bradie? Something around 145-148 in the FP is her maximum (generally overscored Team Trophy results shouldn't be counted for anyone). She's better technically than she was, but from the point of artistry she is inferior to even russian juniors.
There is no other current japanese, US or korean lady apart from the trio named above that could stand a chance, and of them only Alysa, if she keeps her jumps, is truly serious competitor at all circumstances. For Rika to beat top Russians would require they would have to do two or rather three serious mistakes, You would require even more to have a chance at least for bronze.
It can be seen it even on junior level, japanese young girls from the years after Rika are inferior so far, Americans apart from Alysa have only Ting Cui, who has long term health problems. Two or three Koreans are promising, but for several seasons the picture is the same - they do very well during the JGP stages, but later (JGPF, JWC) their results go down significantly. This can change, but so far only a little concern for the tp russians.
Russians, on the other hand, have 3A, still Alina, Evgenia, Kamila and Daria will be senior eligible for the olympic season, Ksenia Sinitsina can still repeat what she has shown at JGP and during the FP at russian senior nationals. In reality only serious health problems or complete lack of the training opportunities thanks to the current situation could change this. At the beginning of the last season people were sending Anna back to juniors, Aliona wouldn't stand a chance, Kamila shouldn't have a chance against Alysa (at the end even Daria has won over her at junior worlds). Than Anna stabilized her 4Lz, added 4F, Aliona got 3A, Kamila won everything etc. But, such predictions can be still amusing when compared with reality.
if Alina came back, and I have no doubt if she wanted to, she could stay competitive. Having said that, she has also won everything there is to win in figure skating, and I would be totally fine if she wanted to pursue something else. She is young and the sky is the limit! I just hope she is happy and continues tuning all the media gossip out.
Of course..we don't know right now. But that would be one of the biggest surprises in FS history.
