Actually, NO race in the 40K universe is what anyone would call "good". Even the Tau who are the only race that tolerates other races only does so as long as those races accept them as overlords. All the other races are xenophobic to the extreme, only letting others live as long as they're strong enough to stop themselves from being killed.

Weirdly only Tyranids and Orks are the only ones that could be considered neutral. Tyranids exist only to feed and Orks exist only to fight. Everyone else want to rule and/or burn burn the galaxy.