Not forgetting Class H, which switches to a higher power rail voltage when the demand calls for it. (thus reduces heat dissipation at lower output levels)
Surely if the body of the guitar is vibrating then the pickup will be vibrating with it, and this will be added into the movement between the pickup and the string. Pretty neigible though I'd have thought.
Just that the stretches are much easier on the 32", especially if "Double stopping". Eg trying to play a classic twelve bar thing up at the 12th fret (ie playing the guitar part) - I can do it on a32", but really struggle on a 34 inch, but everything is jsut that bit easier wherever you are on the neck.
Personally I find a very noticable difference between 32 & 34", much more that I expected.
String wise D'addario, Warwick, Newtone, and I thing Rotosound make Medium scale strings, and I'm sure there are many others.