That would be one weird movie given how much the characters in Dune think about things rather than talk about them. There are important conversations of course, but... there would be a lot of "Paul thinking about the future" voiceover.
Exactly, Dune is practically unfilmable without heavy adaptation. There's a bunch of that inner-thought voiceover stuff in David Lynch's Dune, but still only a tiny fraction as much as is in the book, and it's frankly really damn goofy (full disclosure: I'm waiting to see how Part II turns out before I decide whether this version, or the Alan Smithee cut of 1984 Dune, is the one I'd be more excited about if someone proposed a re-watch—I love that glorious mess)
