You missed one contrapuntal aspect: canonic polyphony. This is easy, though...using a shift register (something like, say, Intellijel's Shifty) and some adept clocking mojo, you can easily offset a melodic line canonically by whatever amount of clock pulses you desire, depending on what you have on hand for clock pulse tampering. It's like the 2b example...but really is more of a "2d" since you can control the temporal shift and therefore the contrapuntal behavior.

There's a lot to play with in your post there...lemme think about the #4 issue for a bit...