Come to think of it, some of the tracks on Kraftwerk's Radioactivity album are the first links in the Ultravox/Be-Bop Deluxe/Tubeway Army train. Songs like "Radioactivity" and "Antenna" come to mind. After those, you could place the Ultravox songs you mentioned, then the futurist stuff from the Drastic Plastic sessions, then Numan. Don't forget, Be-Bop covered lots of other new ground on Drastic Plastic as well.
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