The point about the eclectic selection of Bowie tracks from 1969 to 1975 represented here is that the man himself chose the tracks (as well as the album title and cover shot).

This is why the album coheres so well even whilst seeming to omit key tracks like "Life On Mars", "Drive In Saturday" and "Starman" to say nothing of other big UK hits like "Rock and Roll Suicide", "Knock On Wood" and "Sorrow".
The sequencing of his three best rockers of the era "Jean Genie", "Diamond Dogs" and "Rebel Rebel" in particular, is genius.
Don't forget this was the first compilation of Bowie's early best and it stood out deservedly at the time as an interesting, intelligent and intriguing selection which set it apart from the crowd, something Bowie was rather good at in those days.