Numbah 1 baby, at least here

Exzeal (PC)
EmperorIng - 10,325,290 - 6 - Unit1
Turns out (as some of the other players figured) there is a lot of optimization you can do in regards to scoring. Playing 'normally won't get you much, but waiting for the right time to kill bosses with the multiplier (thanks to their destructible bullets) can make the difference of millions of points. At least with unit1, trying to find the right place to shoot a charge shot and crank up the multiplier can be a fun meta-game. Or rather, it's the only game. I don't know why you'd want to play this if you didn't have a thing for seeing your score shoot up. As it stands, the steam leaderboards are pretty barren (ranked 13 here, lolol).
Stage 3 is still really lousy with its 'physics'... and stage 6's hazards can border on silly.