But his career began earlier, with Space Oddity, which I didn't notice until much later. However Cygnet Committee is a much better indicator of things to come because it is dystopian. It also features Rick Wakeman playng rock'n'roll harpsichord.
The Man Who Sold The Word, was notably covered by Cilla Black and Nirvana. But the dystopian theme really culminates with Diamond Dogs
My favourite Bowie album is probably Hunky Dory but The Rise and Fall of Ziggy Stardust and the Spiders From Mars runs it close.
Bowie is also responsible for some iconic images on covers: Aladdin Sane or with Twiggy on Pin Ups. The latter covers Pink Floyd, The Who, Them, among others.