I've read only a couple of this list - Atwood and Le Guin. Loved both of them.
I never thought of
Left Hand of Darkness as a book about women though. I thought it was more about gender identity and challenging perceptions of sexuality and relationships. But I guess if you're desperate to get Ursula Le Guin on the list, why not? As far as I'm concerned it is a "must read".
(EDIT: Just noticed it's in Wikipedia under feminist sci-fi so what do I know?)
Some of the others I'd like to get around to reading some day: Octavia Butler, Simone De Beauvoir, Sylvia Plath and Edith Wharton (loved
Ethan Frome).
But I have to say, I don't know anything about the rest of them.
I was expecting to find
The Female Man on there by Joanna Russ. I haven't read it so I can't vouch for its quality, but it's a novel I've often heard mentioned in the context of feminist novels.