Of course it should win in other categories, but this article was specifically about Best Picture. Anyway, glad you agree with three of my choices. :)

To your other suggestions (I realise you've used the year the Academy awards were held, rather than release years - I'll use the latter):

1933 - King Kong is my winner that year, followed by Duck Soup. But I love The Invisible Man.

1968 - 2001: A Space Odyssey. No contest. An absolute travesty that this landmark of cinema was overlooked.

1980 - As per my honourable mentions, I can't choose between The Shining, Raging Bull, and The Empire Strikes Back.

1982 - E.T. The Extra-Terrestrial. No contest. Absolutely criminal that it didn't win.