I don't think something as large as ethnicities (so a huge number of people, adapting culture across centuries and continents) can be *defined* as good or bad.
I'm obviously biased (I think the whole gadzei for gadzei, Roma for Roma attitude is a dead end, and feel that acceptance is more important here - that what I am is different from the people who surround me, and it's just as valid, no more or less) but I don't think the world works that way.