DO you think the Indominus-rex is pure evil? I do as she was killing for sport and had a sibling but she ate it so she isn't tragic or amoral. She has the highest body count of any villain in the franchise and is worse than the Indoraptor.
No; murdering her sibling was entirely Offstage Villainy. The carcass in her paddock was what the crane gave to her. Technically, it would've been the worst crime she ever committed, but we never see it and it doesn't leave any impact in the story.
It's true she crossed the Moral Event Horizon and it's likely she has moral agency, but like I said, killing her sibling would've been her worst crime. That would've been even worse than her killing those herbivores, because killing her sibling would've been her most personal crime. However, there's no true indication that she did that at all. Ratigan was disqualified because him "drowning the orphans" would've been his worst crime, but it was still Offstage Villainy because we never see it happening and it doesn't leave an impact on the story.
Yes; the Indoraptor can be sympathied with because he truly was a tragic figure, being tortured and abused by Eli Mills and his goons just so he could be auctioned and Mills would get rich out of it. Also, the Indoraptor didn't deserve the gruesome death he got, as Blue could've at least showed him what he was doing was wrong via raptor communications and lived a happy life with him together instead of being alone.