Never heard of that shock. Once the nitrogen pressure is set, then most leave it alone until the shock needs to be rebuilt. So basically, no need to mess with that.
Is the person that originally got the shock about your weight? That would help determine if the spring rate was good for you. For example, say the person that got the shock weighs 225lbs and you weigh 200 lbs, should be good. But if you are like 170 lbs then the spring is probably too stiff. I would assume that shock has adjustable spring pre-load? That might need some tweaking.
As for the fuel mapping, how does it run? If it runs fine then don't worry about it. Not sure if you have read much on advrider.com yet, but they seem to love a map from a user named Xlratr. On my Stelvio, I tried that one and had lots of decel popping (bike had an aftermarket more open exhaust). Tried the Beetle map and it fix 99% of the issue.
For the luggage, I thought it was all great. I certainly would not change it just for one that is a wee bit better. One thing to consider, if you are really going offroad in challenging conditions, you might want to run bags on the sides vs. the hard cases. Put your unbreakable stuff in side bags, breakable stuff in the stock top case ... then if you dump it on the side you don't mess up an aluminum side case. The Stelvio is no different from any others in this situation, same thing with a GS or Super Tenere, etc.