F&E, what a teaser. Like the greatest writer of all time, Asimov left me eternally hanging. What a jerk
(jk)
It seems Daneel did not overlook the solarians, as he actively directed humanity and the galaxy for over 20 millennia. As I've re-read the series a few times now I've convinced myself:
-Trevize and the others were certainly emotionally handled by Daneel as to make them agree with Daneel's plan. Trevise's ability of perfect decision making is not equivalent to knowing why. His curiosity can be viewed as the innate portion of indecision.
-the solarians are not an enemy, but a farm. As the millennia continue, from where will Daneel find biological brains to replace and upgrade his own? The solarians are only as dangerous as a weapon cache. It is the user of the weapons that does the damage. At any point the solarians can be dealt with. Their tech is pathetic and they experience isolation as freedom. They are no direct threat. The infamous "stare" down between Trevize and the solarian child is just that- acknowledgement of the inevitable. The child is the death of individualism, Trev said it from the get go, "he'll be the destruction of us" (excuse the innacurate quote).
-Gaia is the body, Daneel the brain, solarians the hands, and humans are the moral heart. The heart may seem as the brain at times, but ultimately the heart merely guides while the brain decides, the hands move, and the body connects.
I really wish Asi had the time to write a few more down the line. The outside invaders would have been awesome to meet. The impending crisis with solaria also would have been awesome as well. After all, the solarians had stayed isolationists for 20 millennia, before someone de-activated their nuclear guardians, murdered a ruler, kidnapped a child, and exposed them to the existence of far superior tech.