Yes it is spite. Donna alone can win the majority. Star is tough but she's not THAT tough to fight both of them at the same time. It's kinda like making a "Daredevil vs Captain America and Batman" thread...
__________________
Azula: My mommy didn't love me so I'm going to burn down your village.
Kory has always been portrayed to be able to take Donna 2/3 times.
I've myself always thought of her to be in a strength level somewhere slightly above Donna. At least back in the day.
So near light-speed is a non factor for you guys then?
I thought this was very debatable because Starfire has a huge set of intangibles compared to the likes of Cassie. She is a born warrior and Cassie is still learning. Donna would be the obvious trouble, but I gotta stand by Kory's speed and Nova blast.
Kory was never stronger than Donna. Donna was consistantly the stronger woman. However Kory had edge in experience and firepower.
Unfortunately for Kory, Donna has been upgraded as shown in the Return of Donna Troy special in which she pawns Starfire and the rest of her team.
Starfire has the advantage in speed and firepower but Donna can match her speed and deflect anything coming at her. Cassie has also apparently reached the low Class 100s so she'll also be a threat to Kory.
She simply can't take both of them. Donna alone can take her down.
Back in the day, Starfire was usually the better but Donna's New Cronus upgrade has made her nearly as strong as her sister and moon goddess abilities to boot as well
It sucks because they have so much room for expansion and they haven't done anything with it. Nobody has the balls to pick her up and flesh her out. I also feel like she'd actually have a chance to be something in the JL. It's like she's a fully grown adult playing in the minor leagues.
They practically strapped her to the Titans. Had her freaking pester Wonder Woman of all people.