Immigration should be about genuinely wanting to be a part of that society, because you hold similar enough values that you would feel a part of that society, and you would also be seen as part of that society.
Attempting to get into a different country only for the quality life, while perpetuating the same values that makes your native country a shithole, is currently what's wrong with immigration.
And simply saying "Right, intelligent immigration only" doesn't guarantee social stability. Because, for example, a smart black African won't necessarily give birth to smart children. Countries like Canada, which let in people of vastly different ethnic groups only if they're smart, result in this problem. From my own experiences, we have generally competent first gen immigrants, but second gen immigrants are a complete disgrace.
I mean, it would hypothetically be possible to make a 'super-nigger' race where they were consistently as smart as us, but it would take some goddam serious eugenics.
So which immigration should be allowed? Limited Intra European immigration. Enough so that a German who wants to live in England can do so, but not enough that the groups start to blend. How you can look at someone's face, and tell generally where they're from.
For "Euromutt" countries like Canada, Australia, New Zealand, I think we should be allowed to, to some extent, return home. It's something I aspire to do in the future. Though some significant impurities exist in these countries, you can still see European roots. I can look at friends who have been here many generations, and I have correctly guessed (at least vaguely) which European countries they've come from.
On the subject of different races trying to get into Europe, there's so much moral depth you can get into over subjects like colonisation and asylum and such. I guess I would side with the following things:
a non white can acquire permanent residence in a European (or Euro colony) country if he has a skill he can bring to the country. Even then, it's sketchy, because many of these countries have lower standards than European countries, and don't practise medicine, or engineering, etc... to the same level of quality as we do. And even if we do let some of them in to practise, they shouldn't be allowed to reproduce with Europeans.
In times of acute crisis (such as the Syrian civil war), asylum should be granted en mass to civilians in immediate danger, but of course on heavy conditions. Firstly, if they commit a crime, immediate deportation back to their home. Secondly, they cannot have children or attempt to marry into Europe. Thirdly, they must return home as soon as it becomes safe. Fourthly, they must live independently of our own municipalities, and must work in the vicinity to pay off their costs. Remember, asylum status is not for comfort, it's for safety. It's not an excuse to get into Europe, and they are by no means entitled to our standard of living just because of their own country's problems.