I feel these two films are a very good cinematic take on the book and it's themes. It pretty much left out a lot of the intrigue of other aspects of the Imperium (which I actually don't mind) - like the Spacing Guild (and yes, the film mentions the fact that without the Spice, interstellar navigation would be impossible); but they were also a great motivating factor for the Emperor to take out Duke Leto and especially Paul Atreides. In the film, the Emperor's motivation is that Leto is popular with The Landsraad and could ascend the Throne, but as he "rules with his Heart..." the current Emperor sees him as weak.
It also doesn't really do a lot with the Mentats or the fact that aside from one world (Ix) - computers and AI tech are outlawed and non-existent but in the film the Arrakis planetary tracking system the Harkonnen have appears rather high tech for the Dune Universe <--- But these things don't negatively impact the story being told (IMO). I think they did a good job with the portrayal of the Fremen and the Fremen leader Stilgar too.
I love the portrayal of the Baron Harkonnen, Raban and Feyd <--- FINALLY, screen versions of these characters that IMO capture the book versions a lot better. And they really did a good job with showing what manipulators the Bene Gesserit Order is.
IDK if they'll attempt
Children Of Dune or any of the other sequels, but if they do, I'd be interested to see it.
(I hadn't been following any production reports and didn't really look at any trailers; so when I saw Christopher Walken as the Emperor sitting on the throne, I guess I'm a weird Nerd, because the first thought that came into my head was: "More CowBell."

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