This might be a long one. Sorry.

I enjoyed this (and the first part) but, probably because the book is one of my favourites of all time, I'm a very very very tough audience for it. So for it to score 4/5 despite that is pretty good going, really.

So here goes a good/nitpicks breakdown. Spoilers a-plenty:

---The Good---

* Chalamet's performance as Paul was very good. He really sold the fast maturing of the character, the shift from follower to dictator, etc., effectively, and it's probably the best work he's ever done.
* Similarly, Butler's Feyd-Rautha was outstanding in the relatively little he had to do. He took the part and made it his own.
* Generally, most performances were decent (other than one, which I'll come onto in the 'bad' part).
* Music, sets, cinematography, all excellent as you'd expect fully from Villeneuve anyway.
* I quite liked some of the choices they made - for instance, although I missed Alia as a character on her own merit, the way she was portrayed worked well and meant there wasn't the fear of goofiness to it all.
* The assault on Arakeen and the Shield Wall was suitably epic in all the best ways. It's a real same they spoiled the worms' attack in trailers as it deserved to be seen first-time on a big screen.
* The pacing was much better than the first part, too, and it didn't drag at any point.
* The fights were well-choreographed. The battle between Paul and Feyd in particular.
* Chani getting a bit more to do was a welcome shift, but...

---The Nitpicks---

* So, I have to address the big one first. The change to Chani's character was quite a big shift, and giving her more agency and scepticism was good, but having her effectively directly opposed to Paul at the end was a big, big change, and I'm not sure that works. Especially if DV wants to move on to do Messiah - an off-screen relationship fix (given there's a 13-ish year time jump in between) would be very unsatisfying. If he was just ending here and not going forward with anything else, it might have worked to a point. Hard to know until we see what he does with it, I guess.
* Some of the other fundamental plot points that were chopped out were disappointing; the death of Paul + Chani's firstborn, for instance, was a huge omission for me. The lack of Thufir Hawat entirely (and Paul's status as a mentat to boot) was a real shame, and Hawat's status as PDV's replacement would also have given Stellan more screentime, which would have been welcomed!
* Further to this: no Harah? For shame! That introduction to Fremen life for Paul was such a great part of the book.
* A holdover gripe from the first - Jessica is FAR too scaredy/nervous in this. I guess it's consistent, but just doesn't vibe with her character for me.

---The Bad---

* Christopher Walken was utterly terrible. I was never keen on his casting in the first place (and I like him generally) but he really did not fit this film at all. He just doesn't have the gravitas or the chops for that role, and it just felt jarring.
* Stilgar was a bit too "comic relief" at points, and that felt really forced.

On the whole, it was good, and at some point in the future when I've got the time I'll sit down at home and watch both parts back to back, marathon style.

It's still the best adaptation of a book that probably is nigh-impossible to do full justice too (I do have a soft spot for the Sci-Fi channel version, and if they'd had the budget and scope this one did, hmm...) but as a Wanky Book Purist™ it did fall short in a few aspects for me.

But still a pretty damn good effort on the whole.