Naturally there are minor quibbles about some of the adjustment of the true story for dramatic affect. Edith was much to young (she was actually well into her 40s), the spurious use of the coming war as a dramatic tension builder is unlikely to have been real - Basil started excavating in 1938 and the discovery was complete well before war was declared in '39. The character of the RAF pilot cousin was, I think, a complete invention - the photographer on site in 1939 was actually a woman and Peggy remained married to her husband until the 1960s. I suspect the crash of the aeroplane into the river is a complete dramatic invention. I'd never heard that Uncle Robert had any direct involvement with Basil and his wife, but it might have happened.

Setting those quibbles aside - after all it doesn't claim to be documentary - it is a classic bit of rose tinted English nostalgia where everyone is in their place and knows it. (see The Go Between etc etc). 

The first half cover the development of a non-relationship between Edith and Basil which is never going anywhere (this is not the Go Between, despite the use of a child to link the protagonists across the class divide), so it then has to switch to the triangle between Peggy, her closet gay husband, and the dashing dishy cousin. But it is all a bit obvious.

Good points - interesting use of sound - music and dialogue crossing between scenes to give an impression of a character's interior life. Well photographed, the flat Suffolk landscape comes across and the interiors, like the pub scenes, work well. Ralph Fiennes plays Basil Brown very well.

But overall it is just another feel-good everything is alright with the English world bit of nostalgic propoganda.