So many good ideas here. Blade Runner, Logan's Run, Ren & Stimpy & Zelda top my list out of the themes already mentioned. One other that I haven't seen anyone propose, but has been on my mind a lot would be the Cold War. Seems like a lot you could do and be somewhat of a history lesson as well. Playfield would consist of streets of East/West Berlin and backglass could be Graffitti on the Berlin Wall or some nice propaganda styled artwork.
Modes could include:
Checkpoint Charlie
Berlin Airlift
The Wall
The Bomb
Fortress Europe
Cuban Missile Crisis
Mutually Assured Destruction
Space Race
Mr Gorbachev tear down this wall!