A "female Tarzan" if you will, or perhaps "ninja". I consider this idealistic. I'm not so picky about how it manifests form-wise though. It's mostly the function and the way they can move and carry their bodies and perform very graceful and athletic feats that I consider driving whatever form that takes to one that is idealistic in my eyes.
But form-wise I do think it helps to be well-rounded... not too top-heavy or bottom-heavy so that the figure excels in the widest range of motions. I can't ever imagine someone resembling Kim K being able to perform half these motions... so it does constrain the range of forms quite a bit. But there's still quite a bit of room for variations to possess what I consider idealistic from a functional standpoint.
Another example that isn't quite as lean as the other two and a bit bulkier, but still idealistic in my eyes based on the extremely wide variety of motions she can perform skillfully:https://youtu.be/cOyr2640oeY
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