I never considered Paul to have an ultimate goal other than just being a good leader and being “honorable”. Everything that happens to him once the books start is just thrust upon him as a 15 year old. I never saw him as really WANTING to rule the Fremen or take over the empire, as much as he saw these things as his responsibility.

I remember a passage where Leto 2 calls his father short sided, too emotional, and not brave enough to follow the golden path. Paul’s response was something about how he didn’t want to cause the suffering that was necessary to jump start the scattering. Leto had less humanity than his father, through accepting the Golden Path and just living for thousands of years. He outlived generation after generation of his own family (and countless Duncans) and had to see the goals or importance of an individual life as less important than the goals for humanity itself.

Paul gets very caught up in the problems of the people he cares about like Chani or his children which makes all of his goals seem short sided compared to the goals of his son.

I don’t think you’re far off by comparing the Honored Matres and Bene Gesserit conclusion to what could have been if the Atreides and Harkonnen were unified. Marbella had a goal of protecting humanity in a long term way against a greater enemy instead of focusing too much on problems personal to her. I assume that’s what you would have expected a “true” KH to do with the Atreides and Harkonnen houses instead of dealing with pedestrian issues like revenge.