So what you are after is bad books with decisive (and thus unrealistic) heroes? Did you ever see Hamlet? Notice anything? I have bad news for you: pretty much all good books feature indecisive heroes. It's the villains who tend to be decisive - partly because we know less about them, but mainly because decisiveness stems from a mixture of zealotry and ignorance. Or bad writing. As soon as you any realistic person depth, then weaknesses flood out. Hobb is a far better writer than Donaldson, but it will take you another decade of experience to realise this. That's not to say that you will start to love her books, but at least you should by then know the difference between good and bad. Donaldson is one of those flashy writers who appears good to younger readers - I'll confess that I liked him in my early twenties - but later you realise that his style is really bad. I actually can't read the man's books any more, and haven't been able to for over a decade: I just turn into the editor that the man clearly needs.
As for the original question: I'll agree that Dune probably comes closest - it's just a shame that only the first part of each main trilogy is worth reading. SF tends to go in a different direction (SoIaF is about people, SF is usually about things) so that kind of huge saga is pretty rare. Where it happens, it's on a smaller scale. Roger Zelazny's Amber series is on the SF/Fantasy border, but it comes close. Some of C J Cherryh's early stuff, particularly Cyteen, might be worth a look - she takes rigid third-person PoV to the limit. I would actually aim more towards historical books - SoIaF is stolen (as everyone knows) from the Wars of the Roses.