Overall, Peacemaker is reasonably faithful to the comics. Some details might be tweaked for the screen adaptation, but the core elements remain intact. The characters and their arcs are largely consistent.
It depends on your perspective. Peacemaker has complex traits and actions. While he may do things that seem heroic in some situations, his methods and intentions can be questionable in others.
In the comics, Peacemaker isn't defined by racism. His actions and motivations are driven by other factors such as his beliefs in justice and peace, though sometimes they might be misguided.
Not necessarily. The butterflies in Peacemaker might have been inspired by the comics but could have some creative alterations or additions made for the show.