Without getting into the merits, I think that Wilders has made a major tactical error in the Islamic emphasis. Simply touting the high achievement of his people, and the overreaching meddling of a bureaucracy in Brussels, that obviously does not respect Dutch culture while pushing so-called "Refugees," would have garnered almost all of the same voters as the Islamic emphasis, while picking up those Dutch who would be defensive over his policies as they might undermine those ex-colonials, who have not been antagonistic to traditional Dutch culture.
I realize that the situation is complicated; but this is a tactical gut reaction.