An interesting post. One thing I'd like to comment on is the notion that the expansion eastwards is purely to tap into low-cost labour. The evidence from the A8 countries is that they are on average more likely to have degrees than the native population, and more likely to have degrees than non-EU migrants, who the government are supposed to be able to 'control'. There are builders, plumbers, care workers and fruit pickers among their number, without a doubt, but there are also economists and scientists, doctors and software developers.
The thing with much of the debate around migration is that we hardly ever actually hear from any migrants. They have no official representation in elections, and a very rarely given a platform to speak in the media, but all the evidence suggests when they are given a platform and a voice, then they can actually be pretty persuasive as they help to break down many of the mental barriers that exist.