Greivous was a hero of his people if you look into his backstory
Many people who supported the CIS weren't evil, they just wanted to get out of the corrupt and inefficent Republic
He literally did nothing wrong in the movie. In the show, he blew up some medical frigates and genocided the Nightsister fucking shits
which is more of a favor to the galaxy given how many times they fuck over other people.
Dooku and most of the systems that joined the Separatists weren't bad. They were actually a lot like the rebels and wanted to leave the republic because of it's corruption.
The "heroes on both sides" thing is to show that the Clone Wars is like any war. You have Palpatine manipulating the Republic and Jedi, a character who is clearly a villain.
outer rim dislike the more central worlds and the republic because of this favouritism towards worlds closer
dooku grevious etc are saviours in there eyes getting rid of dictating republic
sheev sure knew how to twist people
Holy shit, I forgot how poorly written that was.