My biggest complaint was that Chani came on too strong, that she turns her back on Paul, and the last shot is of her — which intimates that she’s going to oppose Paul. That would be a disastrous rewrite of Messiah. I trust Villeneuve won’t turn Chani into the next Rey.

Well, that's exactly what they did, except there was no way to actually make her the lead. If I had never read the book, or more to the point, if the book wasn't my FAVORITE NOVEL OF ALL TIME, I would have probably enjoyed it. But the more I think about it, the angrier I get. Honestly, the level of butchery here is just as bad as the '84 abomination, if not worse. Adding stupid shit like weirding modules and heart plugs aren't as bad as turning a minor character into a nasty Fedaykin warrior bitch who actively works against Paul. And devoting so much of the run time to that, which was not only NOT in the book but completely ran contrary to it, was just unforgiveable.

First and foremost: completely omitting the Guild from the ending. It was their fear of the destruction of the spice that cemented Paul's ascendancy to the throne. Without the Guild, the other great houses couldn't do shit.

The Baron was not only evil, but also a child molesting queer. Big shock that modern Hollywood left that part out. The alphabet people would never have approved.

Chani was the daughter of Liet Kynes (a man in the book) and the niece of Stilgar, who was Liet's brother. And as I've mentioned before, she was a minor character who was never anything but loving and supportive of Paul. She was also not a front line fighter, although she did kill one Fremen who sought to challenge Paul for leadership.

Thufur Hawat survived the Harkonnen attack, and actually went into service to the Baron later. It was Hawat who masterminded the plot to have the slave Feyd killed in the arena to not be drugged. He died at the end of the book, refusing to assassinate Paul.

In the book, two or three years pass between the events of Part 1 and Part 2. Alia is born and is toddler aged, fully possessing the knowledge and life experiences of generations of her female ancestors but trapped in a young child's body. She is considered to be an abomination, straight up creeps people out and enjoys it. And it is her who kills the Baron, not Paul.

There is no "Northern" versus "Southern" Fremen in the books. They are just Fremen. They do get progressively tougher to deal the farther away they are from the settled areas. Paul becomes their leader by conducting numerous successful campaigns against the Harkonnens, utilizing his advanced Atreides tactical training. The prophecy thing played a big part as well, but that was just a part of it.

Jessica is the daughter of the Baron and the Reverend Mother who first gives Paul the gom jabbar test.

The official story about the defeat of the Atreides was that it was Jessica, not Yueh, who betrayed them. The Baron did not want it known that he had turned a doctor with Suek conditioning into a traitor. Halleck was convinced of this, and actually tried to kill Jessica later. Paul had to talk him down.

Lady Fenring's husband was the emperor's best friend. He was completely omitted from the book. Also omitted is Harah, the widow of Jamis who Paul takes on as a servant. That's kind of minor, though, since they didn't really do anything.

There are more, but I'm tired of typing.

Feyd tries to assassinate the Baron by hiding a poisoned needle on the thigh of one of his boy toys. The only reason the Baron survives is because Hawat warns him about it. Hawat still hates the Harkonnens, and actively but subtly pits them against each other. The Baron rightly never trusts him, and poisons Hawat early on, while having the antidote to the poison added to his meals to keep him alive. At the end of the book, the Baron has withdrawn the antidote, and the poison kills him. He dies in Paul's arms.