I'm not a Supraphonic or Super Sensitive expert. I have a 1966 Supra and I actually just picked up my first 1965 Super Sensitive last week.
Based on my limited exposure to compare the two, I can initially say wire choice makes a big difference. My Supra has Puresound Super-32's and the Super Sensitive has original Ludwig 10 strand individual adjustable wires. My Super Sensitive has a very dry sound, but it's very "sensitive". The wires extend over the entire resonant head surface and can be individually adjusted to just touch the head surface. Plus the individual wire adjustment allows you to tweak any single strand that is tighter or more loose than the other strands.
The Super Sensitive was marketed towards orchestral musicians, because of the many wire options, the ability to fine tune the sensitivity and the easy of quickly changing between snare types. There were multiple types of snares available; 10 strand wire, 15 strand wire, 18 strand wire, 24 strand wire, 10 strand gut, 6 wire/4 gut strand, 9 wire/6 gut strand, Nylon strand and Nylon-Wire strand.
I'll defer the rest to the experts.
-Tim