Midori Ito and Tonya Harding are unmatched in history. Nobody ever had jumps that impressive. Ito in particular was just unreal.
Midori Ito was amazing, a force of nature, and undoubtedly the best ladies jumper of all time. According to Wikipedia, she achieved the following:
--First lady to land triple Axel
--First to land 7 triples in long program
--First to land triple/triple combination
As to Tonya, despite her career ending in such disgrace, she was also a very great jumper. Her triple Axel, when she had it, was the only one in the same class as Midori's.
Some years back, Kristi Yamaguchi commented on Midori and Tonya as jumpers. Kristi said Midori was incredible, but that Tonya's jumps were perhaps even better, just in terms of natural height and flow. Kristi obviously would have been observing their jumps as closely as anyone in those years.
Midori wins over Tonya hands down, though, as she was much more consistent over a longer time frame than Tonya. And Midori never lost her triple Axel, whereas Tonya did.
Personally, I also think Yuna Kim has to be considered probably the third greatest jumper of all time. Although she never got the triple Axel and doesn't perform the triple loop, the technical perfection and consistency of her triple Lutz/triple toe combination, and her other triples, puts her up there. Many ladies have done the 3Lutz/3toe combo, but none so often or so well as Yuna.
I think it's premature to compare Yuna Kim and Gracie Gold. One day, Gracie may be every bit as good as Yuna. There seems no limit to her potential. But she doesn't have the track record of Yuna yet, and that's important. It's one thing to land a perfect triple Lutz/triple toe at Nationals when you are in ninth place; quite another thing entirely to land it at the Olympics when you are in first place and carrying the hopes of a nation.