Re: self-thinking machine
Why would anyone chose to remember the dreadful Dune prequels written by Brian Herbert and Kevin J Anderson? Dreadful abominations that on many occasions directly contradicted Frank's original work. And don't get me started on the atrocities that were their sequels to Chapterhouse: Dune. Badly written, badly plotted, they have no redeeming qualities.
Plenty of better AIs in fiction than the dreadful Omnius and Erasmus, heck Wintermute and Neuromancer would be a good place to start.