I have finished reading Chapterhouse Dune. My fools errand is finished. It’s not good, and of course ends with loose ends.
I think my personal recommendation is reading the first two books. Although just one or even zero are solid choices. Three is alright, except it’s a trap if it makes you curious and want to read more.
I’m tempted to revisit Heinlein who I haven’t read in at least twenty years, but I’m also afraid he’ll be disappointing.