I'd say 70% of her downfall was willingly accepting the Dark Side every time a black pip came up. The two things that put her over the edge were:
1- Smashing the eggs of a large creature (think Rancor sized apex predator) that was infringing on the hunting grounds of a group of low-tech natives
2- Blowing up a medical space station full of wounded Imperial soldiers who were to be discharged from the military
Personally, I think the morality / conflict system in FFG does a good job of encapsulating the binary nature of The Force. Star Wars is a space opera with a clear line between what is Good and what is Evil. The Dark Side is always lurking, in the form of black pips, ready to provide assistance in a dire situation.