JT, on point (a) yes I agree...thats what they're there for! On point (b) yep, I'm sure the full 5deg is not applied/necessary at higher weights/faster speeds.
My own view on the 'stand on skypointer' term is that it can lead to confusion for ab-initios converting from a typical GA type where (usually) the AH uses a top mounted pointer...i.e. the index moves instead of the roll pointer. This sometimes causes confusion in the first sim session (the roll indication appears to be reversed), but soon becomes natural. Maybe Boeing worried that the inexperienced might revert to type in the engine fail scenario and apply the wrong rudder as a result?
The slip ball in older B732 sims is near useless and could be very misleading as a means of determining PRIMARY rudder input.
In the real world a surging engine failure could result in the ball shooting from one side of the indicator to the other. Not much use in controlling the situation if you've developed the habit of using it in isolation.
BTW, the trick to preventing the roller-coaster ride on engine failure is to apply the correct rudder per the approved method and then HOLD IT. Cycling the rudder just creates almost uncontrollable PIO.