Spaniards have a deeply rooted history of conviction and nationalism. Refugee or migrant populations are somewhat welcome in Spain. It is just put quite plainly through words, action, and demeanor that Spain prioritizes its identity over that of the migrants. Other countries with strong national identities like Germany or the UAE have also been largely successful by prioritizing their natural citizenry over their adopted ones.
If Spain has integrated the Roma people well into its population and society, then it can be done elsewhere in Europe. However, it takes a nation that is proud of its diversity and not too proud and snobby to allow that there are people who act and speak differently that can contribute something.
Since Spain has integrated the Roma population well, other countries should try the same tactics as Spain. This task will not be accomplished easily but with determination it can be achieved. There needs to be a structured way the other countries should take and not go about this in a way that is not full steam ahead.
People make things overly complicated for no darn reason. For some reason people have their own personal grudges against certain people. If people would just mind their own business and live their life, then it would not be that hard to get along. So yes, this can be replicated again, but takes a mature society.
Yes, I do think that other countries can call this a success, because Spain has opened their doors and accepted a different culture into their country. All of the other countries in Europe need to follow their example, and do the same thing, so that the people have fair rights.