[Flyndaran]

I think our idea of racism might be backwards. In that people of olden times hated anyone that wasn't exactly like them and from nearby. The go to for humans "us" is very tightly defined, and "them" is literally everyone else.
Racism was just as much about defining "us" in broader terms as it was in tighter race terms, I imagine.

But coming up with a different definition of "us" would do well to bring home the idea of alien alternate realities.
Just because modern societies place so much importance on "race" and religion, doesn't meant that that's how it must be for all human alternates.