Denis Villeneuve won't be able to outdo the mini-series. He should just start with Book 4 adaptation.

I think the Dune and Children of Dune miniseries handles the details of the first three books very well. A film format can never outdo a miniseries format because there simply isn't enough time in a 2 hour~ film to go into all the details.

Furthermore if Villeneuve adapts the first three books yet again, it would just be redundant because the miniseries already covers them in depth.

I think he should just start with book 4. The events of book 4 happen over 3000 after the events of book 3 and most of the characters are dead so there aren't too many continuity issues. A person who has watched the miniseries can easily figure out what's going on. It's not even that necessary to learn the events of the past as the events from book 4 forward stand alone.