A young idealistic hero who innherited their powers from their parent tries to convince his relatives to stop their Empire's endless quest for galactic conquer and mass genocide.

I'd at least say Viltrum had better motivation than Homeworld. How they view might making right and the desire to control, and the dehumanizing elements of that power.

Homeworld had many of the same methods, but did it worse, as they completely wipe out all life. And the grating fact that there was never any stated reasoning behind it. They did what they did just cause.