I would suggest that you look at the highest population percent location for different ethnic groups and turn them into ethnostates with some modifications to make sure they are geographically in self sustainable locations
You only need a small ethnostate area for each group and the rest can be multi-ethnic
If people of one race persecute another then other people can move to the ethnostate
This encourages better behavior in multi-ethnic zones
@RegalBeagle
Also if the laws on the books in multi-ethnic regions were simply enforced instead of giving exemptions for certain ethnicities then those ethnicities would not be so harmful
I would suggest that blacks, arabs, Muslims, Indians and Pakistanis do not commit as much crime per person in their home countries as in Europe because they are not given an exemption from punishment based on their ethnicity in their home countries