It's a terrible, terrible idea, not the impression I'd like to give of the UK at all.
We have an 80%+ urban population. The theme is backwards looking, nostalgic, completely unrepresentative and uninspiring. Jerusalem is something sung by old women at WI meetings. It shows a complete lack of any creative imagination.
If the world wants to see the great British countryside, I suggest they go and see the real thing. Not an artificial, chocolate box, mock-up built on ex-industrial wasteland in east London.