I just recently rewatched the new Dune and it has it's own special vibe. Certainly knowing the book helps to understand many things and this is true that the power of mentats was clearly not explained at all and this is unfortunate, but a director has to choose on what to focus. To be honest, he doesn't really focus on guild too - Lunch has a really fine scene that demonstrates the power of the guild and Villeneuve is completely missing something like this.
Still I love the new Dune and I love Lynch Dune too, especially the fan made extended cuts that are extremely brilliant.