I think I'm going to re-read the last two books of Dune. I think they might say something a bit different to me now. I think in particular the Honored Matres may depict the media portrayal of man-haters who seek to replace the patriarchy with an equally fucked up authoritarian matriarchy, whereas the Bene Gesserit are a sisterhood but welcome male allies (Miles Teg, Duncan Idaho, etc). Bene Gesserit also know and are in complete control of their bodies. No law could stop a Bene Gesserit sister from getting an abortion, she can eliminate unwanted pregnancy with her own immune system.
I think really where the comparison falls apart is that it's a cabal instead of a movement, and of course there is the rule against Love. Still, I think HOD and CHD will be my next books after Feminism is for Everybody.