2) Roughcast seems to be a good mag switch for a pickup with perfect tone but not enough bite
3) A5 sounded like... well just a pickup to me. I think A5 is a well chosen standard, it seems the most versatile from what I heard hear. A4 just seemed boring to my ear
4) A3 and C8 were nice and jangley, but I understand their outputs are very (Polar - LOL) opposite. Good choice to brighten a pickup.
5) A2 was smooth, full sounding (the low mids!) and probably would be my choice of tone.
Excellent demo, most informative demonstration of magnet differences I've ever come across. I'm an engineer so this kind of variable control and full investigation really gets me goin!